One pet peeve that gets to me is something that's done on a lot of commuter railways and S-Bahns, the 10/20 minute schedule. The schedule looks like:
2:10
2:20
2:40
2:50
3:10
etc, when it should be like this:
2:10
2:25
2:40
2:55
3:10
This minimizes waiting and allows for frequent service every 15 minutes.
What are your pet peeves?
Another pet peeve of mine is a service that is branded incorrectly. A "frequent service" that only runs every 20 minutes. A surface tram being called a Stadtbahn with a U sign indicating rapid transit. A regional rail network that has trains every hour or worse with no central frequent section being called an S-Bahn.