I don’t think you can codify it more than “they do it by gut.” I think it’s pretty rare that a song goes unaltered from the spark in somebody’s head to mastered recording without many changes. It’s a collaborative effort that involves the producers and friends as well.

I think the more somebody is knowledgeable in musical theory, can read and write notes, and maybe even has perfect pitch, the more fully formed an idea will be when it gets to the early stages of recording. But musicians are not all Mozarts.

I dabbled in making electronic music for a while as a hobby. There was only me, I don’t remember anything from musical theory class in school, can barely read notation - in short: I’m not even mediocre. But even I felt occasionally that I needed to speed a track up or down. It’s a gut feeling.

I know from a drummer friend of mine that performing live is hard. You’re either very good at keeping time, like, you have an unshakable metronome in your head, or the tempo naturally speeds up. That’s why during production a lot of musicians get the metronome via a click track in their ears to make sure they don’t deviate too far from what BPM they wanted to hit. During live concerts I think a lot of drummers, as the metronomes of the band, get a click track in their ears as well. And there may be concerts where a song is sped up compared to the recording on purpose, but is still played with a click track because it sounds better live when it’s faster, maybe because it’s missing a lot of stuff from the production that filled gaps at the lower speed. So you can say everything has a tendency to speed up live but sometimes tracks that are performed faster are an artistic choice.