Why isn't Jayce played in high levels very often?

I honestly think Jayce is really OP, due to his crazy range and poke along with speed-ups for the team and a gap closer after he chunks you out with said poke._ He has a max hp spell, absolutely destroying tanks._ He also brings utility to a team, he can be a power farmer, he can sit back and just poke all day, or he can play a "rush it down mid" kind of team comp. It just doesn't make a lot of sense to me as to why this guy isn't played very often. Maybe his mobility isn't the greatest but_ that's why you ward!_ I'd like feedback just because it befuddles me as to why this hunk of a man isn't played.