Facebook's is compounded by the mysterious newsfeed algorithm - if you're infinite scrolling a limited set of items in chronological order it wouldn't be as bad. But I've seen things in my newsfeed and then not been able to find them again if I accidentally closed or reloaded my tab.

If you noted who posted/shared it you can find it on their profile, but if all you noticed was the headline or image on a shared item it might as well be gone forever once you lose your place in the feed.

I wouldn't say that's the main reason I don't check my Facebook feed anymore, but it's one of them.