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What do you call someone who doesn't know their worth or is under-performing their potential?

marked as duplicate by ermanen, FumbleFingers, RegDwigнt Aug 25 '14 at 18:54

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  • It's not even clear what part of speech you're after. You can use your very own underperforming. Or underperformer. Or any number of synonyms a good dictionary or thesaurus will supply. – RegDwigнt Aug 25 '14 at 18:56
  • heh this question is self-referential – Fattie Aug 25 '14 at 19:00

The most common term is "underachiever".

underachiever: a person (and especially a student) who fails to achieve his or her potential or does not do as well as expected.

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