It seems to me likely that the correlation isn't causative. Most folks that start out on Steemit bail, after not achieving expected results. Them as stick it out tend to learn how to post better content, and be focused on realistic goals, rather than quick cash.

As a result, after the time invested necessary to achieve 60+ rep, the posts they are producing are of higher quality - or they have developed relationships with accounts capable of delivering higher rewards.

I do appreciate your analyses.

Thanks!