I tried explaining to someone the fact he was sending over amended PDF single pages for a 200p book that were output completely differently from each other was a bad idea.
EG. Some CMYK some CMYK+Spots, not using a common standard. I explained tat he should send me the whole thing over instead either as one file or adhere to a set standard. He also didn't want to hear about PDF/X etc as they had done it this way for years, they do this thing 140 times a year and they are a 'big' agency blah blah blah.
He saw this as time wasting as he would have to reproof the whole 200 pages instead of just approving 5. Who cares that when the books were printed that the amended 5 pages look completely different to each other and the original 195 pages.
I guess we can all recognize ourselves in this role.
Sometimes it is very frustrating, however there are times that you have to deal with client that you want sales to handle it, in those cases from my experience, let the sales deal with clients, that is their specialty and you will save yourself couple of grey hairs for sure.