nervous Nellie

n. Informal, pl., -lies.
An unduly timid or anxious person.

An investor who isn't comfortable with investing and the risks associated with it.

Investopedia Says:
If a nervous nellie ever does decide to invest, he or she is likely to liquidate the investment at any time.

An unduly timid or anxious person, as in He's a real nervous Nellie, calling the doctor about every little symptom. This term does not allude to a particular person named Nellie; rather, the name was probably chosen for the sake of alliteration. [Colloquial; c. 1920]

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