I know this has been discussed before, but a search mostly turned up discussions on HDiff and MVS trad grades. My current moan is slightly different.
I've just come back from El Chorro where I climbed lots of easy sport, but the UKC and Rockfax gradings are a little out from my experience and the topos produced locally. The issue is that there are so many subdivisions on the UKC grade-voting panel that you often can't vote for the grade you actually want. This is mildy annoying for users but must really limit the usefulness of votes for reassessing grades (and if the grade is ever reassessed the old votes will make the new grade look wrong).
For example, I climbed some routes given 4+ which I think should be 4 and (vice versa) but the lowest I can vote a 4c is a 'low 4b'. If I (hypothetically) contact the moderator and they then change the UKC grade to a 4a, it will look like I (and everyone else) thought it was harder.
A few climbs were much further out - for example
Tira-mi-su (5a) at Escalera Arabe is a 4a currently masquerading on UKC as a 5c! Notice the votes piling up for 5a - the lowest option.
Could the voting panel be expanded? Or more radically could we scrap the 'hard' and 'easy' options? Can you really tell an easy 4c from a hard 4b?