Sorry!!! I was in a rush because I was in a Spanish Test and had to finish it by 3 (had to go to work). I just wanted to answer before I left and didn't have time to explain.
It is constant because it doesn't increase or decrease and just continues to go in a straight line. I hope that makes sense. I'm not the best at explaining.
I actually had that happen to me as well, they downvoted all of my posts and every question i've asked. I wasn't really bothered by it though seeing as hearts shouldn't really matter. This site is more for asking questions when you need help and getting the help you need or helping others. The hearts are just a bonus. Who cares if you are on the leaderboard or not, that's just my opinion though. I'm sorry that this bothers you and I too wish it would stop happening because it is rude. Although, it really doesn't matter to me because it's not about the amount of hearts you get.