To begin from the very beginning without the aid or advantage of something that is already prepared or completed.

What does start from scratch mean?

: to begin from a point at which nothing has been done yet Nothing like this had ever been done before, so we had to start from scratch.

Where did starting from scratch come from?

The expression 'start from scratch' came about in 'handicap' races where weaker entrants were given a head start. Other sports, notably golf, have taken up the figurative use of 'scratch' to mean 'with no advantage - starting from nothing'.