Germany has their public transportation systems down, and they got them down flat (aka, they know what they are doing!) Except for the Japanese, we are unsure that there is any other system in the world that is as on time and with it as the German train system (although we were pretty impressed by the quantity of trains when we were in Copenhagen). The system in Germany is massive. There is almost nowhere you cannot get to by train or bus, street car, metro, or whatever else the option is. It might take some time, a lot of transfers, and good planning, but it is possible.
Although he grew up in Germany, public transportation is something that she has probably had more experience with here. While he drives, she commutes to work by train about 25 minutes each way. In two years, she can only think of one time the train was cancelled in the morning and caused a problem trying to get to work on time. Otherwise, without fail, the train shows up exactly when it is supposed to, and in the worst of all cases, comes five minutes late.
Of course, the train system is not always this perfect. We have had our fair share being annoyed at late trains after long days when we just wanted to get home after a long flight or something. The trains often do not run very late into the night...probably the biggest annoyance...making planning important. Trains in Germany are also not particularly cheap. With this being said, there is always a way to find a deal. Buying your ticket in advance, using group discounts or weekend specials, or just buying a discount card (good for one year and gives you 50% every ticket you purchase) makes it possible to commute by train and not feel a big strain on your wallet. When compared to the USA and Amtrak, German trains look cheap cheap cheap, so we are not really complaining.
There is a reason for the stereotype that Germans are punctual...their trains are part of the proof.