I guess it depends whom you ask this question. Here is QAs take on this subject:

  • When testing provides continuous feedback, developers understand what is good, what is unreliable, and also what is important.
  • Continuous corrections towards the goal speed up the time to completion.
  • Testing isn’t a role with its own goal, QAs are there to help; and the most important help is speed, and the second one is quality (acceptable quality can be met in many ways, with testing it is faster.)

Someone might object and say “on the contrary, with all their phases and complaints, testing makes
things much slower!” however this might stand true for some.

“Good testing makes software projects go faster”

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