There is a lack of follow through. Basically things happen and then everyone acts like they never happend because it's time to jump to something else.
Yeah, but it's more than follow through, it's consequence.
Look at the c-cest scene, I like that scene, probably the best one in the film, but it happened in an empty room and at the end of the day, nothing that important happened.
Nothing happened to Shaw, that thing we just heard about 20 seconds ago is out, and that's about it.
No, wait, that's not true, after she run, roll, jump and escape a falling ship she clutches her stomach once, I think.
Sure, her baby killed white hulk at the end, but it wasn't something integral to the plot.
Now compare it to the chest bursting scene from Alien.
The reaction is legendary,
and it's legendary for a reason, John Hurt fucking die (but live forever in our nightmares) and it's pretty much what kick the movie into gear and into a full blown slasher-film mode.
I mean, the film's antagonist is born there.
That's a big deal.