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Blogginlägg   •   Sep 14, 2014 21:07 CEST

Andreas Cederholm

I came across this article (in Swedish) about how Exploratory Test (ET) and Tour testing can be a good complement to scripted/manual testing. It covers problems and benefits associated to the approach.

When I first skimmed through this article I thought “there are some things I don’t really agree with”. After reading it more thoroughly it more became “there are a lot of things I don’t agree with at all”.
So since there is no way to respond to the article directly I will do it here.

First we probably need to talk about definitions.

I will assume that when we talk manual tests we mean tests written down in detailed step by step instructions then executed by a human tester with an expected result, sometimes also called scripted testing or checking (more about checking can be found here: Which by the way is a great way to kill a tester’s spirit.

My interpretation of ET is in line with what James Bach says here (

When I talk about session based testing (a way to manage ET) I mean Session Based Test Management (

There can of course be other interpretations for ET and Session Based but this is the original source.

Ok so let’s get on with the comments (Swedish quote from the article then Translated to English).

“Under tiden dokumenteras testförfarandet. Detta för att det ska gå att återupprepa scenariot vid avvikelser, följar upp testet samt återupprepa testet senare.”
“Meanwhile the test procedure is documented. This is so that the scenario can be reproduced on anomalies, do follow up on the test and to reproduce the test later”

  • How much you should document depends on a number of things, e.g. what kind of product you are testing, how long time you have, what the stakeholders need and so on. The documentation can be in rigid step by step (for e.g. regulatory or law conformance), session notes, screen recordings or simply kept in the testers mind. You should always think about what the purpose of the documentation is and if the worth of it outweighs the cost of documenting.
  • Although if you file a bug then it probably is important to have clear step by step instructions so developers, the future you and possible other stakeholders can understand what you did, how you did it and the impact.
  • If you during your ET testing find a scenario you think is worth repeating you can of course note down the steps and possibly automate it but one of the benefits is that you often don’t repeat a test since there is often more value in doing a new test (can be rather similar but not exact the same) rather than repeating it.

“Exploratory testing eller Utforskande tester (UT) kan vara ett bra komplement till din testning och dessutom kan denna typ av tester vara en mycket effektiv metod för att hitta de där retsamma buggarna som annars brukar slinka igenom – om dessa tester görs på rätt sätt vill säga! Det är en allmän uppfattning att UT hittar fler kritiska buggar än traditionell testfallsbaserad testning eftersom testaren kan reagera och undersöka mjukvaran utifrån dess beteende istället för att strikt följa ett testfall. Frågan är bara hur man ska göra för att lyckas med sina utforskande tester och undvika riskerna?”
“Exploratory test can be a good complement to your testing and also this type of test can be a very efficient method for finding those pesky bugs that otherwise slip through – if these tests are done in the right way that is! It is general belief that ET finds more critical bugs than traditional test case based testing since the tester can act and investigate the software based on its behavior instead of strictly following a test case. Question is what you should do to succeed with your exploratory tests and avoid the risks?”

  • First the article talks about that ET can be a good complement and then that it finds more critical bugs, in that case I would say it should be more than a complement. Although going by James Bach “To the extent that the next test we do is influenced by the result of the last test we did, we are doing exploratory testing.” it is hard to understand what the other testing (that ET should be a complement to) is.

“Det ska sedan en lång tid tillbaka sitta i ryggmärgen hos testaren att kunna använda sig av alla olika teststrategier och tekniker för att garantera mjukvarans kvalitet.”
“It should since a long time back be second nature for the tester to use different test strategies and techniques to guarantee the quality of the software”

  • This needs to be said, we can never guarantee the quality of the software, we can however give information about what we have seen/not seen and our impression about the software.
  • And yes, it takes time to become a great tester. As with everything else you need to practice and learn continuously to become better and better but this is not only for ET but for all testing.

“Jag tycker att man med en metod som kallas Tour testing slår hål på den myten till viss del eftersom testerna här kan anpassas till testarens erfarenhet och systemkännedom.”
“I think that you with a method called Tour testing can puncture the myth to a certain degree since these tests can be adapted to the testers experience and system knowledge”

  • You don’t need Tour testing to adapt the testing to the tester’s experience and system knowledge, you can do that with ET and the right guidance and education. Tour testing is just one way to approach the product in different ways. You can also use personas where you take on the role of a fictive person. Maybe it is someone that is impatient, someone that is lazy and use all shortcuts or someone who want to exploit the program (think security). You can also use the different hats technique and so on.
  • Tour testing isn’t a replacement for testing knowledge. Tour testing is a technique and hence you can with practice become better at it. It is not something that magically makes testing simple.

“Min uppfattning är att UT framförallt kräver styrning, mål och dokumentation för att vara effektiv och inte erfarenhet.”
“My view is that ET above all requires control, goal and documentation to be efficient and not experience.”

  • First off I would say that then it is not ET. Of course we might want some kind of control (e.g. by using SBTM) but if control and a clear goal is the important parts then it sound more like checking. And that control should be more important than experience seems to me as a lack of trust in the testers. I would translate it to “I’m the only one who know what to test so do exactly as I say”. This is for me as a tester a horrible place to work in. As a test lead, trust in your team is very important. Of course trust needs to be earned and new testers might need some guidance in the beginning before they have shown that they can be trusted fully. But to rank control above experience and skills is to me just plain wrong.

“För att belysa riskerna med UT kan man dra en parallell mellan testaren och en turist som ska åka till London för första gången utan att göra någon som helst research om staden innan. För att upptäcka staden vandrar turisten planlöst omkring på gatorna i hopp om att stöta på roliga och intressanta saker. Troligtvis kommer turisten att stöta på en och annan intressant sak, men utan någon förkunskap blir det svårt att förstå vad det är och betydelsen av upptäckterna som gjorts. Det här gör inte upplevelsen speciellt rik eller kvalitativ och framförallt är risken stor att turisten missar massa intressanta sevärdheter eftersom tiden rinner iväg när denne planlöst går omkring. Turisten vet inte heller hur stor staden är så det blir svårt att veta hur mycket som finns att utforska. Om detta översätts till test av mjukvara så förstår vi snart att stora risker uppstår. Visst kommer turisten ändå uppleva delar av London och troligt är att denne hittar några bakgator och genuina ställen som man annars kanske inte hade stött på.”
“To highlight the risks with ET you can make a parallel between the tester and a tourist that is going to London for the first time without doing any research at all about the city. In order to discover the city the tourist aimlessly wanders around the streets hopeing to bump into fun and interesting things. The tourist will likely bump into one or another interesting thing, but without any pre-knowledge it will be hard to understand what it is and the meaning of the discoveries made. This doesn’t make the experience very rich or qualitative and above all the risk is large great that the tourist misses a lot of interesting sights since the time flies when he aimlessly wanders. The tourist also doesn’t know how big the city is so it will hard to know how much there is to explore. If this is translated to test of the software you will quickly understand that big risks appears. Sure the tourist will still experience part of London and probably find some back alleys and genuine places that you otherwise might not have bumped into.”

  • So many things to say about this metaphor. First, it is very few testers that when they start testing have zero knowledge of the product they are working on and have no idea how it should behave. Even when non testers are brought in to test the product they usually have used some similar product that can act as an oracle (a reference to tell you if the product misbehaves). E.g. if it is a Windows program there are some parts that all Windows programs share (like how to close it, normal shortcuts …) and if it is an app there are other apps out there to compare to. Also feelings is a good oracle, if you feel confused, angry, bored, intrigued or excited can tell you a lot of the product.
  • A tourist still knows what preferences she have and what she likes. Is this pretty, was this far from the hotel, did it taste good and so on. For all those questions we have a gut feeling answer. She can usually understand some signs (at least those with images) to help her navigate and if she can’t that is also good information (think usability). She can find interesting areas that she doesn’t have time to investigate now but if she returns she can spend some time on it (future tests). She will understand if she ends up in a dead end and need to circle back. And day by day she will learn more and more about the product.
  • You can get a lot of information from someone that have no knowledge about the product, everything they find strange is a potential issue from a usability/help documentation view. And if you are a tester hired to test this product you will have more information than Mr. random on the street. Pairing a new tester or Mr. random with an experienced tester is a great way to learn about these issues that the more senior tester maybe have grown blind to after testing the product for a long time.
  • For this to be a real problem we need change the human tourist to an alien that has landed in London and this is the first time seeing earth. It will not know if the air is breathable, won’t understand any signs at all, maybe won’t realize if it hit a wall and won’t understand if it is humans or cars that is the dominating species. Although this would translate to a brain dead tester and not a new tester.
  • Risk of missing interesting attractions is always the problem. But we can of course do some risk analysis or similar to try and find the areas we should visit, but also experienced testers need to do that. When a risk analysis have been done you can easily assign a new tester to one of those areas instead of letting her loose on the whole product (if that isn’t what you want to do).
  • The risk as I see it here is not with the tester doing the ET session but rather the Test Lead (or team) planning the sessions and guiding/teaching the new tester.
  • And by the way it is the back alleys that can be the interesting parts. The interesting tourist attractions (Big Ben, London Eye) can probably be covered by automated checks since we already know where they are, how they look and some have been there for a couple of hundreds or years.

“Riskerna med manuella testfallsbaserade tester kan istället likställas med en väl förberedd turist som innan resan till London läser alla möjliga guideböcker och antecknar vad man vill se och göra under sin vistelse. Turisten kollar upp kartan, valuta, restauranger, transportmedel, väder, evenemang, ja allt man kan tänka sig”
“The risks with manual test case based tests can instead be equaled with a well prepared tourist which before the trip to London reads all different kinds of guide books and notes what to see and do during the stay. The tourist checks the map, currency, restaurants, transportation, weather, events, everything you can imagine”

  • This is a really good thing to do as a tester regardless if you are to create automated checks or run ET. You check old bugs, specifications, similar products, help pages, older versions of the product, expectations and so on to get better understanding what to expect (get more oracles). This is part of the daily work to learn more about the product so you can make better calls what and where to test.
  • The weather part here is a good example since it as with many things in a software project is impossible to predict. A human running a ET session is probably much better in noticing these differences than an automated check or when running a predefined script (since people tend to become zombies when following detailed instructions).

“En stor risk med UT är att fokus endast hamnar på positiva, funktionella tester då testarna inte får någon styrning. Man utgår ifrån det man vet, vilket brukar vara krav eller sina egna erfarenheter om hur mjukvaran ska fungera och vad den ska klara av. Detta är vanligt bland juniora och ovana testare och dessa positiva tester kan i mångt och mycket likställas med ”checking”. Genom Tour testing kan man på ett tydligare sätt få juniora testare att hitta infallsvinklar och angreppssätt samtidigt som man hela tiden bygger på kompetensen och utökar verktygslådan.”
“A big risk with ET is that focus only is put on positive, functional tests since the tester is not controlled. You start with what you know, which usually is requirements or your own experience about how the software should work and what it can do. This is common among junior and novel testers and these positive tests can basically be equalled with “checking”. With Tour testing you can in a clearer way get junior testers to find angle of approach and ways to attack at the same time as you build competence and expand the toolbox.”

  • Why should ET lead to a tendency to only test positive tests? If this is the mindset of the tester how would it differ when creating automated checks?
  • Why shouldn’t we be able to control what we test with ET? It is just a matter of deciding and communicating what parts and with what focus we want to have. This is where the debrief and charter part of SBTM comes into play. In debrief the test lead have a chance to hear what has been tested and can feedback and guide the tester if she is off track by changing the charters.
    There are many ways to handle this and many test conference sessions are about this. You can e.g. use mind maps to plan, heuristics (a fallible shortcut to a solution of a problem) to help remember what different things to test and dashboards to visualize what has and are to be tested.
  • Again here is very little trust in the testers and feels more like an “I know best” mentality. Is this really the case with all junior testers? I would say it depends on the person, how they are educated and guided and not number of years in the testing trade.
  • I don’t agree that if we only run positive tests we can compare it to checking. Checking can be done on negative tests as well (here I assume that negative tests are some test where we expect the product to fail) and if you run ET it is not that you follow predefined steps, you go where it is important to go (depending on current information and priorities) even if it is only positive flows. This is the core of ET and something a check can’t do. And as pointed out, a junior tester doesn’t know that much about the product so if she wants to try something she will not know if it is a positive or negative test.

“En väldigt stor risk med UT som växer med komplexiteten på mjukvaran är att man får en relativt låg test-täckning (coverage) mot vad man borde kunna få med UT. Eftersom människan i sin natur är snäll och gärna vill hitta vägar runt problem så finns risk att testare går runt komplexa delar med knepiga funktioner och testar i de områden/programflöden där de känner sig hemma. Det kan också vara av ren vana som i att ”Jag sparar alltid mina värden genom att använda Arkiv-menyn” istället för att använda de snabbkommandon eller andra mekanismer som finns för spara i applikationen.”
“A very big risk with ET which increase with the complexity of the software is that you get a relatively low test-coverage compared to what you should get with ET. Since man is by nature good and rather find ways around the problem there is a risk that tester avoids complex parts and tricky functions and tests the areas/program flows where they feel at home. It can also be due to habit like “I always save my values trough Archive menu” instead of using the shortcuts or other mechanisms that exists to save the application.”

  • Again with the condescending tone towards testers. People I have worked with that I think of as good testers have never had this approach. This to me is comparable with not reporting a critical bug because it is too much “paperwork”. People that think like this is not testers (at least not good ones). If you have these in your organization you have either made a mistake in your hiring procedure, you have not guided them properly or you have killed their motivation.
  • The issue with defaults and bias is on the other hand a real problem. Although in my mind it is maybe more related to testers that have worked with the product for a long while and have gotten some habits, not for new hungry testers. But it is a real problem and something to be aware of. Rotating testers between different areas can be a good way to minimize it.

“Det kan vara väldigt lätt att grotta ned sig i en viss del av en applikation om man hittar något som verkar avvikande eller helt enkelt drar uppmärksamhet till sig. När man kombinerar sessionsbaserad testning med UT och 80 % av tiden ägnas till denna ”intressanta del” så säger det sig själv att resterande delar inte kommer få lika mycket uppmärksamhet. Hade testledaren avsikten att applikationen skulle testas igenom på en mer övergripande nivå eller med annat fokus kan testet bli missvisande om inte tiden rapporteras på en väldigt låg detaljnivå.”
“It can be very easy to dig down in a certain part of the application if you find something that seems divergent or simply draws attention towards itself. When you combine session based testing with ET and 80% of the time is spent on this “interesting part” it is self explanatory that the rest of the parts won’t get as much attention. If the test lead had the intention that the application should be tested in a more general level or with a different focus the test can be misleading of the time isn’t reported on a very low detail level.”

  • I don’t understand this part. One of the reasons you run Session Based with time boxed sessions is to have a better view of where you should be spending your time and where you actually are spending your time. So what Session Based can do for you is to catch this problem when it occurs since it will be caught in the debriefs and hence give you a tool to deal with it. Without Session Based you might end up with spending too much time on one area but if you have a good test lead it shouldn’t happen.
  • If the test lead had the intention to test more broadly, the test lead should have said so. I guess the test lead have regular interactions with the testers and don’t just hand them the test instructions on stone tablets once a month.

“Som en lösning på problematiken med riskerna inom UT och manuella testfallsbaserade tester finns metoden Tour testing som utnyttjar fördelarna i de båda metoderna. Med UT hittas generellt fler kritiska avvikelser och lite udda saker, medan man i de manuella testerna minimerar riskerna att missa viktiga områden och centrala funktioner.”
“As a solution to the problems with risk within ET and manual test case based tests there is the method Tour testing which use the benefits in both methods. With ET more critical anomalies and some odd things are generally found, while you in the manual tests minimize the risks that you miss important areas and central functions.”

  • How does the manual test minimize the risks? The information and risk analysis you are basing your checks on should also be used when doing ET to decide where and what to test.

The Tour approach is one good way but don’t forget that this is only one way. There are many others, and different approach suits some products or people better and worse.

Drawing the system can be a really good exercise to find unclarities, questions and so on. Although don’t forget that it is often interesting to find out what happens between the districts/areas since that might also be between different responsible teams.

And just to make it clear, I have nothing against Tour testing. I agree with many of the points made in this article (especially in the benefits and conclusion part) that it is a good heuristic you can use to try and avoid missing parts of the product and that it can be a good way to visualize different areas of the product and create some interest in what the testers do. But it is also important to note that Tour testing is not something that is easy and anyone can do well. This also requires that the tester practice and constantly improves in order to become good at it.

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