I delete them from my FL.

I'm very specific with my friend list, I need to know exactly who someone is, and put them in one of the 5 or 6 categories available, and don't want any random strangers on it.
At the same time, I don't want to be rude and flatout refuse when someone sends me a friend request after a nice chat or duty together, so I accept (while planning to delete them later).
But because I don't always instantly think about that the next day, every few days 10-15 names without any association and who I don't remember gather at the bottom of my list.
So when I run upon an orange name that is unfamiliar, it's a great opportunity to remind me to delete them