Sorry brah -
@grinderman was right. She literally is doing nothing. How she won the popularity lottery is a mystery. Watch American Hustle. Why is she even there? She is just brutal and and getting owned by Bale, Amy Adams and Bradley Cooper.
Sorry brah, but you're both wrong.
She won the popularity lottery because she's a good actress. She blew up after a small indie movie called Winter's Bone, in which she played a young girl, looking after her family against terrible odds, in rural America. To be honest, she's almost unrecognizable as "Jennifer Lawrence". She's dressed down, very little make up. Definitely not someone you'd look at and think "Hollywood star"... because she wasn't at that point. But she was excellent.
Her acting chops got her to the place she is now. And also obviously her genetic gifts of being good looking and naturally slim, etc etc etc.
Again, as with all art, whether you enjoy her performances or not is subjective, but I think it's wrong to say that she's objectively terrible and "doing nothing". She's
definitely not literally doing nothing.
I think it's easy to think she's doing nothing, because she's a very natural and relaxed actor. It's easy to forget how much shit acting actually entails, and how difficult it is to achieve that natural and relaxed style. Don't forget, she's saying lines that are not hers, on a movie set with lights, cameras and crew surrounding her, doing take after take after take. If you consider all of that, the fact that she can appear to be "doing nothing" is pretty remarkable.
I think people are so used to the high quality of acting you see in movies, that it's almost impossible to realize how good these people are. If you watched a bunch of "lower" actors attempt the same scenes as Lawrence, you'd suddenly realize just how good she is.
However, you're right that she wasn't amazing in American Hustle, but I think that says more about the character than her abilities.