As the author says in this article, it's not their original idea, but this is the first time I'm hearing about it.

It basically boils down to play a game from your backlog for a bit, and whether you liked it or not, or kept playing it or bounced right off, you now have permission to remove it from your backlog. It sounds very freeing.

I take perhaps a little too much pride in having a very small catalogue of unplayed games (not because I play games a lot, but because I am dreadfully cheap and hardly ever buy anything lol), but even an old miser like me could probably benefit from a little tidying.