@MakeAppPie It's possible that some people don't need the "why", or don't care πBut I definitely appreciate knowing the "why" because, for me, a "why" means that it's a principle that I can remember.
A "how" (again to me) is just something that I can do for that particular artwork, but it doesn't stick in my mind since (to me) it's just a way to do something for that particular artwork. It doesn't always translate (again in my mind) into something I can use in other artwork ...
I'm trying to think of a good example here. Ran into a very good one just the other day comparing two different courses but can't remember now. Old age π
I think it might have been setting up shadow and light for an object. The first course simply said "Do this" and showed setting blend mode to "multiply" and putting a darker colour on that layer to add shadowing. But they didn't explain what multiply did or why that produced shadowing. So all I knew was that I had to select a particular colour, set a particular blend mode and that was it.
Maybe that works for most people? It just doesn't for me π
The other course explained blend modes and mentioned that particular blend modes will turn colours darker and others will make it lighter and how generally anything above "normal" is darker and below is lighter. That stayed with me and made much more sense.