These days I spend a fair bit of time going over the map.  Adding tags to untagged buildings, zapping duplicate buildings etc.  Changing residential to service isn't the worst thing I've seen, my favourite was an apple mapper who retagged lots of highway unclassified to track contrary to the African highway wiki.

There are lots of places that don't yet have the settlements or highways mapped and here we have a highway that has been retagged ten times?

If you think about data consumers and I know we don't usually think about them mapping consistently to something like the African Highway wiki makes life easier for them.   

End of conversation.

John