I realized recently that only 10% or so of the code I tend to write truly benefits from thorough testing. The rest can be handled more broadly through integrati

I realized recently that only 10% or so of the code I tend to write truly benefits from thorough testing. The rest can be handled more broadly through integration testing which is less about the code specifically and more about expected end use cases, like user workflows. I find those tests very useful. I only write those after the flow is established and more or less finalized. I used to write a lot of tests and discovered over summer that it costs too much in terms of time spent writing, changing, and debugging tests for what you tend to get out of it. I do think writing a lot of tests for a legacy or relatively old system is a great way to uncover existing bugs and document expected behaviours. With that done, refactoring or rebuilding is possible and you gain a great understanding of the software.