corki mid

So if corki mid is basically a net-neutral pick (doesn't win lane, doesn't get dumpstered) in laning and he gets outscaled by most other mids, why do people pick him so much? Wouldn't it be better to pick a somewhat weaker laner, fall a bit behind because you play safe and simply outscale? I think there has only been 1 successful corki in pro play recently for NA and EU lcs and even then, Hai wasn't solo carrying his team via corki in a way he couldn't have done on another champ. So mid mains:

1. If you do pick corki, why do you do it? just curious
2. If you don't pick corki because you think like I described above, why not? just curious

I get the whole safe waveclear, decent laning phase where you CAN bully some matchups, shouldn't get wrecked by anyone in laning phase, etc. But in a world of tanky tanks, burst damage junglers and mids and supports, corki has 0 burst mid/late game (because of his range - he will be cc'd and killed if he tries to get burst on squishies and cannot burst a tank) and lacks any cc unless you build rylai's or frozen mallet (very bad decisions). So he seemingly falls off very hard before you have a chance to finish the game... thus you either need to have snowballed hard early/mid or you get outscaled and lose hard. I mean the right mix of tank, cc, and damage from your teammates can make it work late game, but it requires burst damage, tank killing damage (beyond the adc), and tankiness you don't typically find in a team comp to make it work I feel. So I'm probably missing something and just want thoughts on it so I can figure out the logic.