Originally Posted by Riot Taco Storm
Context switching between every game and trying to fill the "last remaining role" in my experience isn't as important. If the last role left to fill is support, and all you know you're at your best when you play Ahri, by all means play Ahri. There's no reason to feel pressured into playing a role you're no good at.
Those are my 2 cents.
While I agree, I would add that if you're last pick, make sure you tell the team "Guys, I'm really bad at support but really good at Ahri, can I please go mid as her?" Because if you instalock last pick as Ahri with no prelude, the entire team is likely going to start screaming "troll", and if no one queue dodges, you may end up reported for refusing to communicate.
If, of course, you ask for Ahri, and the team says "stfu last pick ur support", well, you're kinda boned.
It's why I would recommend at least being competent
in each role, even if you're not good