What's the best idiom/phrase/word to describe someone who has a great potential to do something while he/she is not aware of that potential. For this reason, (s)he underestimate her/his capabilities and asks others to do so for her/him.
There is a huge difference between my question and What would I call my friend's personality? In my case, they are not aware of their abilities but in the mentioned question, they lie about themselves. So, this is another question.