Thanks a lot for your comment my friend.
It is true that small users are simply not aware of what curation rewards are and they often give up before they see it happenening. Or as you said they set their upvotes in a manner that prevents them from getting these rewards.
There is this same threshold now as it was on hive and it is at 5 minutes. If you put upvotes at 4 minutes, you loose a bit reward but you gain because your votes are before all the others.
Dear @achim03 I feel we need to follow these essential details to be making some money. I feel every new user should be aware of these facts as well.