I am guilty of consistently running Vacuum + Mop on dirty floors, and when debris had accumulated, I started ruminating and became worried if the wheels had broken, if my floor was getting scratched, or if something sharp was lodged and the unit was damaging itself. All were false. It took me a little bit of trial and error of "clean this part and resume cleaning."
Roller mop filter vent clean? ✅
Fluffing roller removed and scrubbed? ✅
Roller mop cleaned? ⚠️ Oh wait.. Is it really clean, inside AND out?
What about this hot dog looking thing? [The metal drive shaft (or spindle), the mechanism that actually spins it.] Oof, it's gonna need a wipe if you're feeding it gross floors.