Great point about the retention thing. There are people that don't stay of course but when you realize that people speculate with accounts almost a tad bit like URLs. Then you see things a bit different and process the numbers differently.
I was testing an upcoming search feature for @steempeak interface and was searching a bunch of usernames and most of the results were LVL25 accounts. Not 26... 25. I wonder how many accounts are purely speculative and have never been used or left the lvl25.