The first small success gives an unfamiliar effort somewhere concrete to return.

Starting something you have never done before means working without evidence. Every discouraging hour has nothing to weigh against it, so doubt gets the field to itself. The first success changes that not because it proves you are good at the thing, but because it becomes a fixed point you can go back to: it happened once, so it is possible. Everything after that is argued against a fact rather than against nothing.

When you take up something new, make the earliest goal small enough to reach. And when you reach it, write down what it was, because in three weeks you will want somewhere concrete to return to.