What reason is there to pick Kog maw?

Now before i get downvoted,I'm NOT saying that is crap.

Now is 1 of the 3 adc hypercarries. The other 2 are and . But why would someone pick kog over either of those.

has mobility with tumble. Condemn can act as self peel. She also melts everyone because of true damage. According to the wiki she has the highest attack speed of any champion at lvl 18 (not counting runes,masteries and items).

has self peel with flame chompers. Late game she can choose between long range aoe crits and lots of attack speed. If she gets a kill or an assist on a champion or turret then she can have both.

No mobility or self peel like the other 2.Can deal alot of mixed damage but only for a certain amount of time. He's basically useless when w is on cooldown. His q feels kinda useless since he does so much magic damage. Thematically it makes sense but in game it's meh which is why it's maxed last. W does magic damage do its reduced by mr unlike vayne's true damage.

Also kog has the worst early game of the 3. So why would a player put in so much extra effort with kog when they could pick the other 2 and have a better early game and more overall survivability