That's sounds insane. How does that even work?
For one, kitchens are bespoke to order to each apartment, because the apartments are sized and spaced differently so the chance of the kitchen of one apartment fitting just right in your next apartment is super slim.
And two, how do you do the logistics of moving the kitchen? There's certainly a significant expense of time and money disassembling everything (especially stuff that's glued and bolted to the walls), packaging it, then carrying it by van or freight, then reassembling it again (assuming it just fits and you don't need further investments to make it fit).
How do you account for all these costs? Tell me how renting is cheaper again than owning.
>until you eventually end up in a house
If most Germans would end up in a house they wouldn't still be renting.
I moved with kitchens in Germany. German kitchens are also differnt from kitchens e.g. in the US.
My kitchen is 13y old and I see zero reason to change the front panels either.
Moving all the above things is possible, but a lot of work for little gain.