A question about rank or a rant

So here goes I’m new to the halo games and world but my question is about rankj I understand it starts over every month in the arena but I was wonderingf why is it if your a bronze silver or gold rank weather it be 1 or5 in either rank that you work soi hard to achieve those ranks that if you have a couple if bad games or the team has a couple of bad games that youy staert to lose or goigoi down in rank and in player rank and team rank let’s bve honest some ppl sucj at thus game some are great just think if youy earn a rank or Go up in rank it should stay that way I mean it starts over every month any way

This was created so that everyone has a chance to rerank every month.