To go up in the Tiers you have to hane a certain amount of RANKED games and reach a certain average.
The people in tiers above you may have a bigger average than you because as you advance in rank your average is reset.You then have to play another certain amount of ranked games to level it out to your proper average. And so on as you advance in the Tiers.
Your points level has nothing to do with advancing up the tiers. It only allows you to unlock Equipment in the Pro Shop
Hope this helps.
MEL1950
The more RANKED games you play under your current average score the more your average will go down.