Free win

When you have tried and failed or when your MMR is far above your current rank

WHAT IS PROMO HELPER?

If you lose your promos, but make it back into the series, you'll start that series off with at least one win. This applies to every division and tier up until Gold 1, so you're on your own for promotion into Platinum and above!

In instances where a player elects to dodge any game in a promotion series by leaving the game during champion select, this will result in the account being ineligible for promo helper upon entering the next promotion series.

Finally, if you're eligible for promo helper in a division but you're demoted to the previous division, you'll lose that eligibility. For example, if you lose your Gold III promos, you'll automatically have one win toward your next promo series, but if you demote into Gold IV, you won't have that win next time you enter your Gold III series.

https://support.riotgames.com/hc/en-us/articles/204010760-Ranked-Play-FAQ#h6q2