Stumbling block + one step = what?

Once: You'll be like OTL...

but, thereafter: A 'stepping stone' behind you. Now just put your one foot on it and stretch your arms down on the ground on which you just fell down your face.

Yes, it's just helping you with re-start.

In the distant future, when you turn back and see the path through which you went, it will remind you of the stone(, yeah which once had been a scar-maker), as an essential point.

You can find quite many real stories: Dostoevskiy, Howard Schulze,
Christian Dior, ...(google their stories)