What is the meaning of [Cowards die many times before their deaths]

This proverb is quotation from Shakespeare’s _Julius Caesar_. Caesar says:

> Cowards die many times before their deaths;
> The valiant never tastes of death but once.

A coward often imagines that he is in the point of death when he is not, with
the result that, unlike a brave man, he frequently experiences the fear of
dying.