Depth and breadth in testing

Today i learned about breadth vs depth in testing. Not that the concepts are new to me, but James Bach and Michael Bolton are eeking out the definitions so carefully and precisely in Taking Testing Seriously, that it feels like a whole new framework, and this made space for some good realisations.

The breadth axis defines the variety of types of bugs that a particular test is able to discover, while the depth axis defines whether a test searches for easy win bugs or the hard to find ones.

Dividing the two concepts thus, will help me plan my tests better and communicate to project managers what is possible under certain constraints. And even write better testing strategies.

This is from the book Taking Testing Seriously which I just started reading (and will be for some time considering the breadth AND depth of the publication - see what i did there 😀)