Skin Strip(p)eress aka Sexy Ghost aka The Skinned Ghost (1992): What starts out as a mostly harmless (unless you're the snake who is squeezed to death or the frog who is eaten alive) piece of CATIII horror morphs into a just as harmless Lam Ching-Ying vehicle after half an hour or so. Both parts of the movie are definitely watchable - a Lam Ching-Ying vehicle does after all contain Lam Ching-Ying - but don't include anything I haven't seen done sleazier, nastier, funnier or just plain more creative in other movies.
99 and 44/100% Dead (1974): Sometimes you encounter films that are utterly inexplicable. Directed by John Frankenheimer with a cast led by Richard Harris, you'd expect a film to be at least watchable, but this gangster comedy (parody?) fails on every imaginable level as well as on levels the human mind wasn't meant to imagine. Ironically, the film's problem is not a lack of ideas but rather that it has a multitude of them, none of which is good, or clever, or funny. The film feels like nothing so much as like one of those pseudo-Tarantino movies made by directors totally unable to understand what makes Tarantino's movies work, which is quite an achievement for a film made twenty years before Tarantino's time.
If the film's aggressive tendency to laugh about its own, unfunny jokes weren't enough, there are also scenes that go on and on and on for no good reason but for Frankenheimer's wish to make the same, unfunny, joke three times in a row and horribly annoying acting that reaches from undead (Ann Turkel) to a mugging version of Michael Caine cool (Harris). It's so crap you could fertilize a farm with it.
Heaven and Hell aka Wong Jorn Pid (2012): As far as Thai horror anthologies go, Yuthlert Sippapak's and Tiwa Moeithaisong's (of whom I'd expected something better than this) film doesn't go very far. There are some misguided attempts by the directors to make their simple stories more complicated by adding either a wrong-headed stylistic conceit (hey, why not make an intensely talky story where all dialogue is delivered via intertitles!) or tonal shifts that seem random and ill-advised at best. The problem is, if the basics of your story aren't interesting enough to keep an audience's eyes open for half an hour, adding random crap to the story won't help.