And being delayed for 15-40 minutes, getting thrown out in the middle of nowhere, or having to continue by bus is an inconvenience for most people, but a nightmare for people with disabilities. Imagine being in a wheelchair, having a digestive condition (Crohn, IBS, etc.), or some sort of anxiety. I imagine that there are groups of people in Germany that simply do not travel anymore.
It is an area where proper governance is failing. I don't know about Germany, but in The Netherlands, Dutch law requires at least 90% of the trains to be on time (less than 5 minutes delay). If national train company do not reach those numbers, they are fined and I think in an extreme case they can lose their concession.