What does "Revolving lines of credit should not exceed 40% of the balance." mean?

Question

What does "Revolving lines of credit should not exceed 40% of the balance." mean?

Answer 1

It means what it says, you balance (what you owe on your credit card/ what you've spent) shouldn't exceed 40% of your allowed balance (the amount your allowed to spend, your credit limit,  but you shouldn't spend it all)  

Answer 2

A revolving line of credit is a credit line that you can continue to use and pay off.  A credit card is a revolving line or credit, a car loan or mortgage is not.

Credit lenders like to see that you're using less than 40% of your available credit on credit cards.  Otherwise it looks like you need the credit rather than using it for convenience.  

For example, using less than $400 on a $1000 credit card.