Jennifer Aniston doesn't think she's been as successful as she could've been because she's not "desperate" enough. The US actress admits she doesn't have enough "ambition" and also believes she's missed out on some acclaim because comedy movies don't receive as much praise as serious films. She said: "I've never been looking for it. I mean, maybe that's half the problem. I don't have a lot of ambition. "I don't have that desperation of, 'I've got to have it!' I know how hard it is to be an actor just to begin with, but to be a working actor - you should just be grateful. "And I love making people laugh. I find that is just as valuable as making people want to kill themselves." She added to Metro newspaper: "I felt all of a sudden, 'What have I been doing for the last 20 years?' "You scratch your head and go, 'Was that just disrespectful and horrible?' "Because obviously, comedy is not as revered as drama. But I think comedy is really hard.”