Because not everyone at the same MMR is of equal skill . Maintaining a 50 % winrate is not the same as having a 50 % or 50 % winrate at any given MMR . If you ' re 4 , 5 K with a 50 % winrate over your past 100 games , you ' re probably not improving through what you ' re doing . If you ' re 70 % winrate at 4 , 5 K over the past 100 games you ' re more likely improving at a way faster pace and you ' re probably a lot better than the guy with the 50 % winrate . If you have a 30 % winrate over your past 100 games at 4 , 5 K , you ' re probably doing a whole lot more wrong , due to mental state and other factors , than the guy with 50 % winrate . Boosters are the ones who usually have this low of a winrate . MMR isn ' t the de facto sign of how good you are . MMR in combination with winrate and performances in games are all factors that show how good you are . To answer your question though . Level 2040 accounts . As someone who has recently climber 600 points in less than a month , I ' ve done so through primarily shifting my mental state and try harder . The important part of this has been to dodge more games . There ' s rarely a game at 4 K without fresh accounts . I see people at level 20 with pages after pages filled with losses . You also have the hero spammers who only win with their 12 heroes and it ' s an auto lose if they don ' t get it . 4 K is just a shitshow and I don ' t think 5 K is any better .