The problem isn't that "Hot Tub Time Machine" isn't an especially good movie, because no one goes into it expecting much. The problem is that it fails on its own terms. It has a handful of decent laughs, on average about one every 15 minutes. That's something, but it's not even close to enough, especially in a movie with nothing else to offer.
It's colossally tasteless, but that's not the problem. The problem is that we notice that it's tasteless, because we would never notice if the jokes were funny. The movie's big event, for example, shows one of the main characters getting shot in the penis. You might see how some wisecracks might be ...
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