Why is 'false' truthy in javascript?

Question

I understand that an empty string is falsy in javascript and a not-empty string is truthy in javascript.

However, why is 'false' truthy in javascript, is there anything explicit in the specification? Is it a performance issue or are there situations where you would want the string 'false' to represent true?

Answer 1

is there anything explicit in the specification?

Yes:

The result is false if the argument is the empty String (its length is zero); otherwise the result is true.