It's stupid little details: the train to Berlin main station leaves from different platforms, so there can't be signs pointing people to the right platform. It also leaves from the wrong side of the platform so when you come down the elevator you have to run for several minutes ... to miss it. And then walk back up, go up the elevator, walk to a different platform, and try again.

Meanwhile the announcer rubs it in: "please make sure to be at the correct part of the platform", rather than just having the train do so.