What it does
Keen Eye prevents the holder's accuracy from being reduced by any source — lowering moves like Sand Attack or Flash, or ability-triggered accuracy drops. It also allows the holder to ignore evasion boosts on Pokémon under level 30, though that clause is irrelevant at Lv50 competitive play.
Keen Eye does not improve accuracy above base values. A move with 90% accuracy still lands 90% of the time — it just can't be pushed lower by opposing effects.
In Champions, accuracy manipulation is genuinely rare. Double Team is banned in competitive formats, and dedicated accuracy-lowering strategies are niche. Most games you run Keen Eye, the ability will never trigger at all.
Who runs it
Adoption rates across this group are very low across the board. Skarmory (3%) has the highest — it's there for bulk and support moveset rather than Keen Eye itself, which ends up as a default because the other ability options aren't useful either. Lycanroc (1%), Toucannon (1%), Meowstic (1%), Sableye (0%), and Pelipper (0%) all see minimal adoption. Pelipper's competitive value is entirely Drizzle — Keen Eye on it is irrelevant.
How to use it
The only genuine use case is when you know the opponent runs Sand Attack, Flash, or another dedicated accuracy-dropping strategy. Switching your Keen Eye holder into that position completely invalidates their line.
In doubles, the opportunities to land accuracy drops are already limited — a team usually can't spare turns for accuracy manipulation when there's direct damage and field conditions to manage. Keen Eye in that context is almost never relevant.
Tips & strategy
Keen Eye is honest about being a weak ability in competitive play. That's not a criticism — it's context. These Pokémon make teams for their stats, typing, and movepools, not for Keen Eye. Evaluate them on those merits.
The one situation where Keen Eye has real value is facing an accuracy-stacking opponent with both Sand Attack and sand weather chip. Against that specific setup, Keen Eye completely shuts one half of their strategy down. Narrow, but real.