That's just the thing: Haskell's type system catches many, many bugs that would be runtime errors in most other languages. It can even provide static guarantees against extremely tricky bugs such as race conditions!
sloppy coding
Everybody is guilty of sloppy coding some of the time. Having a powerful sanity check against it is extremely helpful.
ones where you made an error in thinking
Haskell can actually help here, too. Its rigid purity forces you to think more carefully before you act and its powerful expressiveness enables you to build highly composable abstractions that are simply not possible in other languages.
Edit: Check out this talk on someone's personal experience with static typing in real projects at work:
I very rarely have much trouble finding bugs that I made myself. The hardest bugs are the ones somebody else had a hand in. I'm sure everyone wishes they could force their coworkers to be more careful. :)
That's just the thing: Haskell's type system catches many, many bugs that would be runtime errors in most other languages. It can even provide static guarantees against extremely tricky bugs such as race conditions!
sloppy coding
Everybody is guilty of sloppy coding some of the time. Having a powerful sanity check against it is extremely helpful.
ones where you made an error in thinking
Haskell can actually help here, too. Its rigid purity forces you to think more carefully before you act and its powerful expressiveness enables you to build highly composable abstractions that are simply not possible in other languages.
Edit: Check out this talk on someone's personal experience with static typing in real projects at work:
http://vimeo.com/72870631