Definitely merit create in a certain reason, and that is to clean up the numbers of spammers and scammers in the forum. At first, it serve as a basis in recognizing and analyzing all the post in the forum. Secondly, it also the basis of reaching a certain number of merit for you to be rank up. Do click the link for you to much understand about merit. I hope it will help to you. https://bitcointalk.org/index.php?topic=1689727.0