Everybody gets A to Z.
It is as easy as . . . Well A to Z!
What ever your creative project is, you begin at A. Then when you have finished, you are clearly at Z.
You are inspired with an idea and you can envision the finished piece.
You see it is easy.
The common phrase is purposefully hazy about what happens from B onwards up to Y.
Those letters are there, however, and don’t mysteriously disappear even if they are omitted for the sake of short hand.
For a writer, the B to Y of their novel might be six months or more, and if their Z is that novel being published it might the timescale might shift to years.
If you are an artist, the B to Y might be a few days or weeks or even months.
A musician’s B to Y might be a free days to a few years also.
Keep having those A to Z thoughts.
But spend time on the B to Y plan to get you from that A to that Z and be realistic about the process.