When to Apply Exploratory Testing?

August 22 10:00 2013 by Nataliia Vasylyna Print This Article

Note: the article was updated in September 2018.

James Bach, a famous tester and a proponent of exploratory testing called it “scientific thinking in real-time”. Performing exploratory testing, QA engineers design tests and execute them at the same time. Herewith, they create new test cases according to the results of already executed tests.

Many researchers consider exploratory testing not important and even unnecessary technique, due to its informal nature. As with any other testing technique, exploratory testing has its own pros and cons.

Advantages of exploratory testing:

no need to spend time at test cases preparation
no need to follow predetermined test scenarios
provoke cognitive thinking of a QA engineer
possibility to start testing without specification or detailed requirements
critical defects are found more quickly
quicker temp of a testing process
more interesting and creative for QA engineers

Cons of exploratory testing

difficult to reproduce test case
hard to define test coverage
require good qualification of testers

When to apply exploratory testing?

Now, we are going to cover the most typical situations when applying exploratory testing can fully reveal its benefits.

Test Documentation

Testing documentation is ready, but not enough time for testing is left. In this case, a solution can be to create a checklist for the most crucial functions of the product and conduct exploratory testing.

It is effective to apply exploratory testing method, when the software requirements are not clear and detailed enough and a tester does not understand the application complexities. Also, when software specifications are informal or missing and there is not enough information about the product specifica, your can perform exploratory testing.

Exploratory approach is suitable if a test scenario is repeated a lot of times. For example, during regression testing, QA engineers are supposed to repeat the same scenario again and again after each software modification. This reduces concentration and some bugs may be omitted. In this case, exploratory testing gives a fresh view on the product and helps to detect omitted bugs.

Development process

At the early phases of the development process, this testing technique is used to verify the error-prone parts of the software in order to focus testing on them and make necessary modifications.

In case of a sudden change in the product and if it is impossible to elaborate new scenarios and test cases, exploratory approach can be applied.

The product has been already tested, but the managers decide to ensure its quality one more time. Then it is time for exploratory testing.

But applying just exploratory testing one can omit important functional paths and it will be impossible to measure the application testing coverage. So, the best decision is still to combine this testing technique with more formal approaches.