German trains might not be what you expect...

A surprising fact is that German trains might be unpunctual; that's not really what you expect. I once boarded a train 10 minutes later than expected, in a 2 hour trip. In addition, S-Bahn (commuter trains) are really bad in Munich. They come every 20 minutes, but after heavy snowing they can be delayed almost 15 minutes!
On the other hand, subways are precise. I still don't understand how, but the time table is precise to the minute, and you are certain that the subway will be there at that time. I used to take the 8:42 S-Bahn, and I had a 6 minute trip in the underground plus 2 minutes for walking between them. Every time I managed to arrive to the subway station at 8:32, I got to the S-Bahn in time. If I arrived 2 minutes late, I missed the 8:33 subway and was only able to catch the S-Bahn if I ran and nobody was standing in front of me in the escalators.