You are compared to other players, their level, which consists of the invisible Mu and Sigma. -If game thinks you will win and you win, you don't gain much. -If game thinks you will win and you lose, you lose much. -If game thinks you will lose and you win, you gain much. -If game thinks you will lose and you lose, you don't lose much. =Most of the complainments are completely logical. 1.Friends and party you play with affect the comparison of players. In good and bad, some groups level up and down very fast, some seem not to rank at all. You just have a lot more steady Mu and Sigma values in partyed matches than you have in solo matches. 2.Huge win streaks causing no level up and 1 lose meaning lose of rank. Game believes you will win, win, win, win. You won't rank up as fast, you have much higher chance to rank down on the other hand. 3. Lower EXP means you don't have so much history. Single matches affect your Mu and Sigma a lot. Of course person who wins 100 out of his first matches deserves level 50 a lot more than person with 5000 matches of which he has won the last 100. The first one is usually second accounter but his level is still the same old, the second one is just evolving during his long career. 4. If you drop EXP by quitting it means you have been losing making game think you are weaker. Thus game thinks you are likely to lose=Winning gains much.