I think a big problem is that people just don't vote on old posts and you only get paid 1. after 24 hours and 2. after a month, but no payments for votes after that.
If people had the chance to build up a legacy of posts that others could upvote later, it would really help - but they freeze voting and earning after a month, so you really need to make an impact early, otherwise your best work gets unrewarded.
Steemit posts come up in Google searches. I'd like to be able to vote on old ones and possibly comment too. A lot of the information will still have value later.
I really seems that most money is made in the first 24 hours.