Occasionally, you come across a film so great that you can watch it dozens of times and never get bored. It's a wonderful moment, like making a new friend. It's a sign of good film-making to be able to keep a story fresh even if you have visited it many times before.
Then there are those films so terrible that you regret watching them even once. You resent wasting two hours on your life on something worthless, and the idea of spending further time re-watching such garbage would be downright offensive.
Then, there's a third category of film. Content-wise, they're great; a gripping story, stellar acting, high production values. But, for one reason or another, you would never want to watch it again.
Maybe it's too depressing, tackling historical or contemporary issues that you know are there but would rather not invest your leisure time in fretting about. Maybe they're too brutal, too gory or too disturbing. Maybe they just scare the absolute pants off you, and you can't do that to your heart again.
You might love the film, it might even rank among your all time favourites, but when it comes time to choose between putting time into a film you appreciate and leaving yourself feeling desolate, nauseated or disturbed, you'd probably elect to just watch Anchorman for the twentieth time.