Players have a hard time predicting burst mobility

Part of getting better at league is knowing what your opponent wants to do in a given situation.

High elo players have this down pretty well, along with a strong understanding of their opponents options and cooldowns.

Low and medium elo players tend to tunnel focus their own options and opportunities as opposed to reading the opponent beyond a rudimentary level

Burst mobility takes full advantage of this weakness, which is why the majority of the player base often bans mobile champs.

Everyone feels way more comfortable when their opponent has limited options because they are easier to read

Riot keeps adding mobility because they see its frustrating aspects on players as a skill issue, not a gameplay hazard