Everyone wants to blame somebody for a bomb, but the truth is, it all comes down to the producers, the director, the screenwriter(s) and the studio. The studio is to blame for greenlighting the thing. The screenwriter is to blame for failing to produce a decent script (don't get me started on originality). The director is to blame for failing to interpret the script properly (or failing to realise that it was a piece of shite and should never have been made in the first place). Finally, the producers are to blame for failing to keep a tighter rein on production and not saying no to the egotistical director often enough.

Finally, if the actors are actually to blame, they can usually be sacked, right?

*Gets off soapbox.*