Never.
MK
Never what?
Tidy up the lav inflight?
Most of the time when I go back well into the flight, the lav looks like cr@p with trash all over the floor. I know people are slobs, but I think some attention needs to be given and some minor pick up done inflight at a minimum.
That being said, I have no doubt that some of are cockpit brethren are also responsible and would have no problem with a call to the front telling a slob to come back and clean up their mess.
We are in a service business.