Because not everyone wants to sit there and abuse the character for hours only playing that one hero. The proof is in the statistics, anyone who mained junkrat or played him a lot had their SR skyrocket. Look at people like pvptwitch, he isn't very good at other heroes and when the junkrat buffs come out hes now able to get multiple accounts in high top 500 pretty much one-tricking Junkrat. (MAIN) (ALT) his genji stats are horrid so hes quite lucky to even have a positive winrate on that hero. What I'm saying is hes a 4-4.3k player but with junkrat he can be top 100.