Count Dookkake said:
The worst film is a mediocre one.
I'll modify this: the worst film is a boring one. Bad films can often be very entertaining through unbelievably shit direction, script, acting etc. whereas mediocre run-of-the-mill films often don't entertain in any way at all: normal direction, normal acting, normal cliches = boring.
Sometimes though there are interminably bad films in terms of direction, acting, script which are also interminably boring and not entertaining at all, and they are the worst movies ever made.
Therefore, a film like Battlefield Earth does not deserve to be on this list because it is entertaining, whereas After Last Season, from the trailer, seems to completely justify itself as abysmal.
A couple of days ago, I watched Thor: The Hammer of the Gods. This is a low budget film on Thor and werewolves, and stood no chance of being good, but it had the possibility of being entertaining. Unfortunately, it was mediocre, boring and a complete waste of time.