Ranking

On the 13th of the month why does the rank change from where you were the day before? If I played a ton of hours which I do (on average 6 to 8 hours a day minimum and sometimes more) to improve the rank why does it change if I put in the work to have to do it all over again on the 13th again? I have done everything in the trail to gain points in all categories and it's unpredictable if the killer an or survivors are skilled enough to participate correctly. If the killer sucks and everyone does gens then there is no Altruism points. If the survivors suck and leave you facing the killer alone by hiding the whole time what can you do to change that? I feel the rank should remain the same seeing how a player does decent and still not get a rank mark to boost to the next rank. Like you have to almost have a perfect match every time is vastly impossible. But if you do bad meaning the killer is skilled to sacrifice you quickly leaving you no room to play a decent trial then you loose rank marks every time. What is the solution to getting to rank one? Currently rank five and highly frustrated to say the least.