But another way to view why one gets so many challenges...
If you are number 3 on the log.... then you only have numbers 1 and 2 to try challenge.
But if you are number 18000 they let you challenge a 16000 guy. So the lower u are the more options you have and hence less challengers. But when in the top 200, everyone wants to knock you down. Up at 4000.... guys below get to aim at 3600 so will by pass you for example.
If you are number 3 on the log.... then you only have numbers 1 and 2 to try challenge.
But if you are number 18000 they let you challenge a 16000 guy. So the lower u are the more options you have and hence less challengers. But when in the top 200, everyone wants to knock you down. Up at 4000.... guys below get to aim at 3600 so will by pass you for example.