the five-per-day limit seems restrictive at first. it's hard when you want to post all your favorite stuff but you're timeblocked! and it's hard to figure out what you like enough to post ahead of the rest. it's like picking your favorite children.
that said, i think it also kind of works out, aside from allowing the mod team some leniency. (they deserve that!)
it kind of helps to reframe it: it's sort of like picking out images for your portfolio. you post your best stuff first. the stuff you are the most proud of, the stuff you look at and go, yes, that's me! i want people to see me! and i think that's important. being able to prioritize posting your self expression over just arbitrary sketch pages that you don't feel much attachment for.
not that those aren't important, too. i just think it's nice to be able to figure out your own priorities vis-a-vis art and its visibility on here. do you want to be vulnerable? do you want to find out how it feels to be seen, using your art as a vessel? maybe that's not for everyone. maybe it's safer to post things that aren't pure expression if you're afraid of judgement from some theoretical stranger.
but where's the fun in that? :P