Is Ayn saying that the individual is more important than the collective, or that the best route to collective improvement is through selfishness? I suspect it'

Is Ayn saying that the individual is more important than the collective, or that the best route to collective improvement is through selfishness? I suspect it's the latter, but Ayn and her followers frame the debate so combatively that it's hard to be sure. I see this confusion rearing its head throughout this page. (I read the first 100 pages of Atlas Shrugged, and got sick of it. I thought it was uninteresting as a novel and inefficient and not rigorous as a treatise. This part of the novel seemed to intentionally perpetuate my confusion: the conflict, as I recall, was between truly selfish people and collectivists that were too incompetent to see when the selfish people were doing collective good. Why conflate incompetence and collectivism?)