People would often ask me why I would just read the code for a project rather than ask whoever wrote it. At the end of 30 minutes talking to someone, I may not have learned anything. Or I may have learned the wrong thing because they wrote it 3 years ago and forgot about it.

At the end of 30 minutes I either understand how the project works at a high level or know enough to know I'm not going to be improving anything with this project, ever.