I noticed that some pools with high hash rate is doing something like an attack.
When difficulty is low, they push max hash rate until block is found and the atacker earn most part of block reward and he left the pool for a while until difficulty decreases. So i noticed that sometime the pool has huge hash rate like 3gh/s~7gh/s at gincoin for example and when block is found and diff increase it has only 150mh/s. It is like a cheat.
So, tiny poor guys like me with my 8x RX570 cant earn shit.

I was mining at zergpool and my reward after 24h mining at 22mh/s was 0.30gin instead 1.00.
But there are other pools that has same attack.

So the best for most users will be the pool that has a stable hash rate.
I was mining good at pickaxe.pro or gos.cx, it has low rash rate but it is stable, but you need to be patient because some days block is not found, but another day can found 2 or 3 blocks. After a week my average earns was higher than the calcs and much times higher than the attacked pools.