I tend to tip specifically, like at a great café or hotel reception I will leave something in the tip jar (which I hope is distributet to the whole team, not just the person that happened to be in contact with me) or at the car wash when they are doing a great job with the interiours.
I would be more generous with tips when travelling to countries where the people don't earn as much as in Germany. Like in Poland a guy picked us up as a group from the airport and drove through the night in the snow for 1,5h up a super big mountain, almost never braking, always in control and at the physically maximum speed possible with a bus full of people. I made sure to stay behind when everybody had already left, gestured to him what a great job that was and because why not I gave him a humble amount of cash as a sign of my appreciation : D
I guess tipping works differently in different parts of the world also. I know that Chinese restaurants they never want tip, noticed that in different countries.
When I was in Colombia the people there were so nice and they were doing you a favour and they did not want to be tipped for it (I speak good Spanish though). Some people there even looked almost disappointed like "Man, I did you a favour, from me to you, for free. I didn't have money in the back of my mind. What are you thinking about me here?"
I prefer giving a "tip" to a beggar who looks like he/she really needs it or a nice street musician who deserves it etc.
-> I'm thinking, is it possible to tip a police officer or people with jobs like that?