I value the commit messages in the context where you develop a tool that has to be run widely.

In particular, I had experience with Wine. Having useful commit messages allows you to do bisects and trace down regressions with more ease than cross-checking messages with some external ticket system, and when you have a lot of people contributing to a project it's easier to see what they're doing when they try to do a patch.

I also believe though, that it is good practice to help your colleagues when they do need to find an issue in a project where a lot of different people can work on.