[{quoted}](name=Chocolate Frost,realm=NA,application-id=3ErqAdtq,discussion-id=EzqlEGTA,comment-id=00000000,timestamp=2018-12-19T12:38:45.987+0000)
I think it was an okay choice by Riot. Teleport was the only summoner spell that could be cancelled, after all.
Imagine if you could cancel other spells to reduce their CD?
Ignite/Exhaust not gonna secure the kill? Cancel so it can be cast again in the next minute!
Cast Ghost to run away, but the enemy immediately disengaged after? Cancel so it can be cast again in the next minute!
Ya know, people LOVE to use the voting system in a way that violates the boards guidelines by simply downvoting things they disagree with but this comment really deserves further discussion.
Teleport is unique in that, unlike other abilities, the cast time isn't a part of the actual effect. You didn't get to move part of the way towards the location if you cancelled it. But everything else with a duration begins the moment you press it. You essentially commit to ignite, ghost, exhaust, and barrier as soon as you use them. Even if ignite didn't need its full damage to kill, or you got away without needing ghost/barrier.
As far as I can figure, the original intent behind teleport's ability to be cancelled was to protect the caster from just getting killed if an enemy found them mid-channel, with the reduced cooldown rewarding a player who correctly canceled to stay where they were and fight. But it ended up being widely used as a trick, with the threat of an incoming enemy being enough to dissuade attackers and the reduced cooldown being given to an undeserving player who didn't commit.
And that's not what it was supposed to be for. It's unfair to the enemy for you to be able to trick them with an animation that doesn't actually correspond to the effect being used. That's why Shen, TF, and Pantheon can't cancel their channels either. They're movement abilities, not deception abilities.