So I got a client not too long ago who had a product built by another company. He hired me to do some fix ups and add functionality because he wasn't very happy with it. I was under the impression (not assumption) that I would be the only one working on the project.

Low and behold I was working on this project because he was hiring this original company to do another project, which is why they couldn't fix the issues they had with the first project. So after they finished the second (which, by the way, was just as shoddy), they were hired to do more improvements on the first.

Some of my code was relying on the original base code that they had written. Apparently my code exposed a flaw in their code that didn't reveal itself right away, so I hadn't known to fix it.

So fast forward a month and they come bitching to me about the problem that I "caused." Instead of just fixing the problem, they insist that I revert a piece of code back to the original. Yes, this will temporarily "patch" the problem in this area. However, there are other areas that are still broken, but just hard to get to.