The biggest problem I find is the "fresh pair of eyes syndrome"
. You see, after been in this type of crack after a while, the brain just doesn't see the dirt anymore, so when a punter comes to have a look, their eye will always pick out something. They expect specific cleaning standards for general cleaning prices. Hence the old "you missed a spot" - syndrome, ha ha. I don't get this though, I'm too slick. I get the guys to check each others work, i call it criss crossing. Its not for them to pick up on each other, rather for them to know that no matter how good you are, your brain just will often not see the dirt. It switches off. Get thm to wear those lamps on there head and then check each others work in grids going north south, east west movements, especially when doing bereavement clean ups. We cant have any of that nasty decomp juice running down from under the bath when the temp rises, yuckh!
Neil