Probably most are temped by the money part of Steemit. Many it is not the main reason to take the plunge, but it will be certainly a part of it.
Once they noticed that their first posts are getting unnoticed, a lot of them drop out. Other keep on battling and try to make something of it.

I belong to the second group. It still is sometime hard to get noticed. But I'm trying to build a nice community around me. I always prefer an comment on a post of mine over an upvote. Both is great. But what is an upvote worth without a comment? Just money but for the rest it is meaningless!