So Microsoft is talking about removing unpopular games from their XBLA download service. This is a terrible idea for all the reasons in that linked article, so why are they doing it? I think there are a few possible reasons:

1. They made some kind of bonehead technological or contractual mistake, such that keeping games available for download somehow costs them money.
2. Microsoft wants to flex some muscle with smaller developers.
3. They are compensating for a craptacular UI.

I think option 3 is the most likely. The Xbox 306 dashboard UI is pretty terrible, everything (games, add-ons, movies, etc) is listed by a short unhelpful title, if you want to see what something actually is, you have to select it, wait for it to load, and then wait again for all the legaleese to scroll out of the 4 line text-box they give you, and watch the description slooooooooly scroll past, with no way to skip ahead, and if you hit any button, you have to start over at the beginning. This is just one of the problems with the UI, the whole thing is a disaster. It's bad enough that the Rock Band people did an update to their game, so that that there was a music download store in the game.

Given this malovelent UI, it's easy to make the case that you would only want the 20 or 50 "best" games on the system, otherwise it's too hard to browse and find the stuff you want. Microsoft, you are solving the wrong problem.