All this depends on the type of users who sign up on Steemit. More than 350,000 accounts have been made so far but we all know that most of them are spammers, some leave early as they don't get rewarded for all the hard work they put on creating a quality content and some are upvoting their own comments by leasing steem power. Having said that, we need to come up with an idea to encourage good, creative users keep using this platform, may be anything like a whales sponsoring a couple of creative writers just to motivate them!