It literally NEVER FAILS. Get into the final game of your series that you have carried yourself to..
And then in champ select: Me: "Hey friends, I can most likely carry the game if you let me mid" Other guy: "nope, mid-- I'm one pick higher than you"
In game: Other guy's score-- Twisted Fate 1-8-7, (how appropriate since he murderered our chances of winning the game) literally used his ult ONLY for vision. LOL. It NEVER FAILS. No problems in games up to series finale, but then-- oh then RIOT fucks you hard.
I just don't get people that take carry roles when they know they are bad. If you are bad, you would be doing yourself and YOUR TEAM a favor by just taking support and backing up/peeling your adc.