Once we stayed at a Springhill suites and left a $10 tip for a 2 night stay. Then we checked out and I remembered I left something behind. I went back to the room, and the supervisor was there already looking over the room, and the tip was gone.I suspect your tip goes to the person who grabs it. So that would be the person that cleans the room after you checkout.
I am skeptical that she gave it to the person who actually cleaned the room. I felt bad about the situation but how can you prevent something like that?