lack of finishing power; inability to score
Primarily used in sports contexts to describe a team or player who creates chances but fails to convert them into goals or points.
Due to a lack of finishing power, the team dropped points.
He increased shooting practice to overcome his inability to score.
決定力 means 'decisiveness' or 'ability to finish', while 決定力不足 is the lack of that ability.
得点力不足 is a similar sports term meaning 'lack of scoring ability', often used interchangeably but can refer to overall scoring rather than just finishing chances.
Compound of 決定力 (decisiveness, finishing ability) and 不足 (lack, insufficiency).