8. Jessica Alba
It isn't unfair to say that early-2000s Jessica Alba was a casting agent's dream: her combination of beauty and likeability allowed her to be cast in a number of high-profile movies, though this sadly hasn't translated to her giving a single good performance to date.
Alba has just two major critically-praised movies under her belt, Sin City and Machete, neither of which benefited at all from her presence.
If anything, her refusal to disrobe for Sin City's strip club scenes drew distracting attention to the fact she was cast because of her star power rather than her ability and her willingness to commit to the movie's bold, R-rated tone.
As for Machete, despite being a main character she's staggeringly dull when stood next to the likes of Danny Trejo, Michelle Rodriguez, Robert De Niro and, yes, Steven Seagal.
Alba's career has taken a backseat to motherhood in recent years, though when she does show up in a movie, she tends to play the attractive yet forgettable girlfriend role. As easy on the eyes as she is, she's otherwise brought desperately little to the table.