I find making up the rooms late - the norm for most Marriotts. If you are not out by say 9am - you room could be delayed all day. Many times I have departed at say 11am and returned at 4pm and the room has not been serviced.

This tends to be one of my beefs with Marriott in addition to many times not be able to check in before 3pm - when rooms are made up. Although since I have been Platinum - I can usually check in upon arrival if after 12 pm.