While the film is rife with continuity errors and several other minor cinematic drawbacks, there are several plots, subplots and character details whose inconsistencies have been noted by critics and audiences.
The Portland Mercury has pointed out that a number of "plot threads are introduced, then instantly abandoned".[17] One of the most notable examples of this is in an early scene, when halfway through a conversation about planning a birthday party for Johnny, Claudette off-handedly tells Lisa: "I got the results of the test back. I definitely have breast cancer."[11] The issue is casually dismissed and never revisited during the rest of the film.[11][17] In addition, the audience never learns the details surrounding Denny's drug-related debt to Chris-R or what led to their violent confrontation on the roof.[17][18]
At the same time, a number of seemingly minor situations are made overly dramatic. One such example is when Mark is revealed to have shaved his beard; the camera zooms in tightly on Mark's face while dramatic music plays, and some dialogue is dedicated to various characters commenting on it, after which the matter is quickly dropped and never referred to again. In perhaps the most infamous example, the principal male characters congregate in an alley behind Johnny's apartment to play catch with a football while wearing tuxedos. Although Denny mentions wedding photos, an earlier conversation states that the wedding is still a month away, and no explanation is ever given as to why the characters all arrived at the apartment wearing their wedding clothes. Wiseau received enough questions about the scene that he decided to address it on a Q&A segment featured on the DVD release; rather than explaining the scene, though, Wiseau only states that playing football without the proper protective equipment is fun and challenging.
The character of Denny has received a great deal of attention from fans for the contrast between his bizarre personality and lack of backstory. Though he is apparently in college, it is never quite clear if Denny is a fully functioning adult, mainly due to his ignorance of social norms; in the film's opening moments, he jumps into bed with Johnny and Lisa, oblivious to the fact that they are about to have sex.[17] When asked about Philip Haldiman's portrayal of Denny, Wiseau stated: "I think he brought a lot stuff. One thing was he's really retarded a little bit." When asked if Denny was written that way, Wiseau says he did so "Indirectly, so he's confused."[11]
Much has also been made of inconsistencies surrounding the operation of a cassette recorder that plays a role in the film's climax. After Johnny begins to distrust Lisa, he hooks the recorder to her telephone. After several days of continuous recording, he retrieves a cassette tape, which, rewound, contains only a conversation between Lisa and Mark that occurred seconds before. When the conversation is replayed, lines are present on the recording that were not said during the actual conversation. Wiseau explained in an interview with LaIst: "You can buy a recorder that records 24/7, and the tape can rewind by itself."[7].