Is it still "wet" after you have finished?
We try to dry the carpet as much as possible with dry passes and blowers. Leaving it slightly damp is acceptable, asking the client to stay off it as long as possible until it is completely dry. Provide the client with overshoes if necessary and some safety instructions about moving from damp carpet onto hard flooring.
Leaving the client with "wet" carpet is not necessary and should be avoided.
Nicky