Most abandoned

Ranked by the lowest median global achievement-completion rate across each game's achievement list (10+ achievements, 500+ reviews). A low median means most players who earned at least one achievement stopped well short of the rest — that can mean players lose interest, or it can just mean the game is long. It is not a quality judgement, and it says nothing about players who never touch achievements at all.

"Median achievement earned by" is the median global earn-rate across the game's tracked achievements (Steam). "Ever started" is the highest earn-rate on record — typically the easiest achievement — as a proxy for how many owners launched the game at all.