I was in Germany in May and I didn’t tip at all for the first 2 weeks. Then I was having a conversation with my aunt and she said she leaves 10% and I began to feel bad about all the places I didn’t tip.
On my last night I took everybody out to dinner and it came out to 190 Euros, so 10% would be 19 Euros. But then I put down 250 Euros by mistake (not recognizing the right bills) and the server came up to me and said this is too much and he gives me back the money.