I'm lucky if a watch 1 episode a day, but on occasion when I find something good I might do 5-6 episodes or even just marathon the whole thing. I always enjoy watching anime, but I like to multi-task to an extreme point where if I am sitting around doing nothing other than watching anime I get jittery and can't pay attention because I'm thinking about all the other stuff I want to be doing. The hardest part is actually starting to watch an episode.
Artwork, animation, sound quality, and character design play huge roles in whether or not I like an anime, so most really old series are unwatchable to me. There is also a large portion of anime coming out that bores me, is in a category I don't care for, or is just not that good, so that eliminates a huge portion of watchable anime. I would say there are about 100 series that are must watch/amazing series for every anime viewer, and that number grows by about 1 every couple of years when a classic is released. After that it's best to ride the coattails of newly airing series while watching the occasional old, less important anime to increase your chances of finding those special series.