When tradespeople don't vacuum up the work area prior to end of day. Cough, cough...dust and stuff everywhere (that vacuum cleaner was left in the area for you to use).
When the person drilling the holes in the wood does not clean up the holes by drilling from the other side to clean up the wood bits. What messy holes result when the holes are drilled one way only-not nice to see. Glad this is not on my tab...parent is not keeping on top of things...