We tend to complain a lot about them. But compared to the US (and I don’t know any other system than US and Germany) it’s far better.
If you don’t take any loans your score gets better and better. If you take out a big loan it is at first negative, but after paying it off it may be even positive.
My mother never took out a load in her life and has almost a perfect score.
In the US you get rewarded for making credit card dept and paying off interest. That is actually a stupid way to handle money. In Germany you get rewarded if you save first and then spend your money.
The problems lie in the details. If you move to a poor neighbourhood your score drops. That is utterly stupid!