It happened to me too. Maid walked in when I was changing my clothes, had to run into the bathroom quickly!
Review by sdrize
In response to review, MariusKapocius says ...
Most cruise ship cabin doors that I have had have a dead bolt that can bolted when your in the room.
This has never happened to me. The stewards always knock first. Thanks for mentioning it, though. I'll be sure to use the "Do Not Disturb" Sign when needed. Sorry to read that it happened to you more than once. I hope that you mentioned it on the survey.