Why should I bother with unit testing if I can just use integration tests?

Question

Ok, I know I am going out on a limb making a statement like that, so my question is for everyone to convince me I am wrong. Take this scenario:

I have method A, which ca

Answer 1

Unit tests aren't about debugging during initial development. They're about design, and they're about adapting to change. My unit tests almost never tell me where a bug is when I'm on my first pass through a hunk of code. My tests warn me when a bug arises six months later because somebody (possibly I myself) tweaked an object whose relationships they didn't fully understand.

Saying unit tests are a waste of time during initial develoment is like complaining that my car gets crappy mileage on its way out of my driveway.