Here one example how confusing and complicated it can get: https://www.openstreetmap.org/way/259031259#map=17/48.88074/10.05814
Himmlingsweiler, a hamlet or district of the town of Fachsenfeld. Is mapped as node as suburb, which should be a neigbourhood or maybe quarter (of Fachsenfeld). The residential area is tagged with is_in:village=Fachsenfeld. In my style rules it will get Fachsenfeld as tooltip but you actually want to see Himmlingsweiler. Best way is to give it name=Himmlingsweiler. There is nowhere stated in the wiki that a name tag is forbidden on the residential area tag! Now you will get this inconsistent mapping. Fachsenfeld is mapped as suburb too. Imho this should be tagged as town or village. That it is part of the municipality of Aalen is already mapped by the admin_districts.