It's like Facebook giving you a loan to run your ads with and you pay later or at the end of each month.
Use it!
Billing thresholds are set based on how much you’ve paid in the past. For example, if you are a first-time advertiser on Facebook, you will be billed once you reach $25 or if you reach the end of the month. After that first payment,you’ll be billed in...
As you spend more, your billing threshold will continue to increase up to $2,500 as you make successful payments.
Then from there it can goes higher as long as they successfully bill your card.
adespresso.com/guides/faceboo…