Fig.: from the beginning

The market situation has changed, therefore we have to rewrite the draft of the supply contract from scratch

Le condizioni di mercato sono cambiate, quindi la bozza dell'accordo con il fornitore va rifatta ex novo

The new toy was really beautiful, but it could be dangerous for little kids, so the company redesigned it from scratch to make it safe

Il nuovo giocattolo era veramente bello, però poteva presentare pericoli per i più piccoli, perciò, per renderlo sicuro, la ditta lo ha ridisegnato ex novo

In racing the “scratch” is the starting line, in old times literally scratched in the dirt. Horses or people racing with a handicap, start ahead of the line; the ones who don't need an advantage “start from scratch”, i.e. from the very beginning