I think it's easy to blame others, but programmers are optimistic by nature and bad at estimating. Also, I think all of us have had the opposite scenario where

I think it's easy to blame others, but programmers are optimistic by nature and bad at estimating. Also, I think all of us have had the opposite scenario where a request comes in from a business-minded person that they think will take forever and it turns out to be trivial. It feels great to do a lot of good very quickly, independent of what the project schedule says.