It's all about the next one.
Some of us get stuck living in the past. Reminiscing on old mistakes bring us back to old habits, or worse, make it impossible to move forward. But you can't fix yesterday's mistakes today. You can only deal with...today.
Jesus knows we aren't perfect, and are going to mess up time and time again (Romans 3:23). But we're called to keep pressing towards the next small win of doing what God tells you to do. You can't fix yesterday's mistakes today. But you can make the next one better.
"Not that I have already obtained all this, or have already arrived at my goal, but I press on to take hold of that for which Christ Jesus took hold of me. Brothers and sisters, I do not consider myself yet to have taken hold of it. But one thing I do: Forgetting what is behind and straining toward what is ahead, I press on toward the goal to win the prize for which God has called me heavenward in Christ Jesus." — Philippians 3:12-14