Anyone who's ever spent a lot of time watching Monty Python knows that it can ruin your life. Examples are numerous but I'll pick just two. First, if you happen to watch a lot of Monty Python you may find yourself reciting certain passages from the movies at parties while drunk. This is guaranteed to get you a laugh or two, but also guaranteed to make certain you do not get a date with anyone at the party. Or anyone who knows anyone at that party. Laugh = good, no date = life ruined. Not that this has ever happened to me! No, never.
Second example. Say you've seen Life of Brian a few too many times. Then say you start watching Rome, that cool series on HBO. Well if you've seen Life of Brian a mere, say, 10 times you're bound to remember the empewah of Wome who spoke wif somfing of a wifp. Actually it wasn't a wifp, he just couldn't say his r's or l's. As in, "Citizens of Jewusawem! Wome is youw fwiend!" So if you do recall that you'll never be able to say to your wife "Let's go watch an episode of Rome." No, indeed. As you've guessed, my wife and I are quite fond of watching Wome.
I think LIfe of Brian said it best: Tewwific wace, the Womans. Tewwific!