Plan 9 is not the worst movie ever made. It is possibly one of the most amateur movies ever made. If the name of the game is entertainment, then you will get it here in the form of unintentional comedy. The screenplay, plot, cliché dialogue, sets, fx, the complete disregard of destroying the legacy of Bela Lugosi, you name it this movie sucks in so many ways. However, it is watchable, only if you have a sense of humor and can laugh at the film itself.
There are worse films out there. Tons. Worse movies would be something that is so amateurish, but that you can't even make fun of it. Here's my all time best movie to make fun of "Laser Mission" with Brandon Lee. This is a great movie.
My worst movie of all time would be Star Wars 7, The Farce Awakens. This is not a movie that you can laugh at. It's a movie you cry at, because it is so sad. Crappy acting, crappy story, killing off a fan favorite character - Han Solo (not mine, but the series), just a modern day action nonsense movie.
Here's another garbage movie: Starship Invasions (1977) with Robert Vaughn, Christopher Lee. This is a truly awful movie. It is so bad, the only thing laughable is the stupid costume Lee is wearing. Plan 9 has nothing on this movie.
Now, here's a movie that some losers consider the worst movie of all time: Manos, The hands of Fate. I don't think so. Manos has a story, some eerie characters that you will never see before or after in any movie. The dialogue is solid. It has atmosphere! There is comedy and I believe it was intended.
Plan 9 has some of the worst writing and production. The dialogue is so horrendous, it's one cliché after another, hard to watch. The plot is a joke in a not so funny way. The fx are crap. What we have here is a filmmaker who was basically an amateur. The film was produced and released, for that he gets an A. As a film it is a failure - F. For the unintentional comedy the rating is a a D-, 2 stars at best. 1 star given for including Bela Lugosi in a shameful way.
Now, since there are over 200 ratings on this "film" and since imdb has gone downhill, where readers cannot opt to view in Chronological order, this review will probably never see the light of day. What a shame. We live in troubled times indeed.