Jack of All Trades, Master of None

Meaning:
Often used in negative light to describe someone who can do many different things, but is not particularly good at any one of them.

Example:
John is a Jack of all trades, but master of none.

Did you know?
This idiom originated from the Elizabethan era, where the term Johannes factotum (“Johnny do-it-all”) was used. The phrase Jack of all trades became commonly used in the 17th century. ‘Jack‘ was used to replace ‘Johannes’ as it was the more common name for a man