I notice that the top 10 in Leaderboard are rather stable.

They may move a place or two up and down, but generally the top 10 remains in the top 10.

It is the last ten that are always changing.

You see them there one day, and they will drop off the next day.

I think that is the nature in all sites.  The 10% makes most of the money (as in 90% of the money) while the remaining 90% makes just 10% of the money.