The Onion A.V. Club has an occasional feature called "Commentary Tracks of the Damned," where they listen to and write about DVD audio commentary tracks on bad movies. The biggest round-ups of these audio postmortems can be found in the articles Commentary Tracks of the Damned and Curse of Commentary Tracks of the Damned.
What can a director say about a terrible movie that bombed? Well, quite a lot, actually. One of the amusing things about these Commentary Tracks of the Damned is how rarely a filmmaker will find real fault with even the worst movies -- occasionally you'll get a director who talks about studio interference or how he'd have preferred to end the film a different way, but even that is sort of rare, and you'll very rarely hear someone criticize his or her own work in a serious way. And there's nothing really wrong with that. You can't expect someone who worked hard on a movie to sit back and point out flaws; when you finish a hard job -- and this applies to any tough job, in the movie business or the real world -- what you tend to feel is pride in having done it, not an inclination to focus on the negatives.
Of course, self-criticism isn't always pleasing to listen to. One of my favorite comedies, Top Secret!, comes with a commentary track where the directors criticize the movie constantly, pointing out the bad structure, the lack of good characters, the jokes that didn't get a laugh. It's interesting and all, but if you like the movie you sort of want to jump into the recording studio and explain to the filmmakers that the flaws don't matter. And it's pretty annoying to hear a director talk about how he would have made the movie differently, when you know he hasn't made a movie this good in 20 years, and his current instincts about how the movie should go are probably all wrong.
Other types of commentary include:
- The commentary where they just describe what's onscreen ("He's walking to the door.. he gets stabbed... he falls down... he's dead"). This happens in both cast/crew commentaries and in those tedious scene-by-scene commentaries by "expert" critics on films where the main participants are dead.
- The "from the vaults" commentary, where an old movie is commented on by someone armed with all kinds of knowledge about the making of the film. I like this kind of commentary because it does what a commentary track is supposed to do, which is fill us in on how the movie was made, how a particular special effect was created, etc. Much more useful than critical commentaries that just tell us how the critic analyzes the film. Roger Ebert's justly-acclaimed commentaries on Citizen Kane and Casablanca are like this; he points out all the special effects in Kane and describes how they were done.
- The "gang" commentary, where people who were involved in the film get together and swap stories and jokes. I'm always a little wary of these, because frankly, movie-industry people aren't all that appealing individually and they are even less so when they get together to enjoy themselves.