Upon saying that, Melbourne's trains are usually pretty good, over 90% on time. It's the buses here that I have issues with. The timetable at the stop is completely useless, and the app is not much better. Sometimes the PTV app says the bus will arrive in 1 minute, and it arrives 5 minutes later.
While true, this is a factoid.
1. Some trains never run. For the commuter this is like a very late train. You need to add the "did not run" numbers to the late trains to get a total effective lateness figure.
2. Some trains run but are so full you cannot get on them. Try catching a train from Prahran to the city at 8am. Nonetheless, this counts as an on time service.
3.On time is defined as anywhere from 1 minute early to 5:59 late. To me six minutes late is not on time.
4. The fraction of late trains is much higher in peak hour, when more people are affected. So the effective late % is higher than it looks at face value.
It seems like there's no leeway in the timetables to make up lost time, and no extra trains parked in the outer suburbs (morning) or CBD (afternoon) to make up services.