I struggled over how to layout the directories in my GIT repo. The fact that I want to build from the git repo is another layer of confusion - as opposed to building from a tarfile. I'm making something unstable for other developers right now, rather than a stable releasable item.
The next bit of extreme confusion is .... where should my package's install target put the binary plugins I built. I'm not going to try to go back and check over this in detail but as far as I remember the docs were very unspecific about that as if it could be anywhere and different user docs on the net seemed to show different things.
I got to the point where I could appear to build the thing on my machine but that's not good enough - the PPA has to be able to do it and then you've got to upload, wait and hope the log explains what's wrong well enough.
I tried looking at other packages - I'm building plugins for GNU make so I tried that - but it was using the build from tar approach (IIRC) and was way overcomplicated for my very simple package which is just a few .so files in a directory.
It took me a couple of weeks of messing around with every possible option to get this far and I just ran out of energy and time. I am not a beginner at programming - only at packaging - so IMO there is a great deal that could be done for the user experience. Don't get me wrong - I'm not picking on .deb. RPM is another incredibly horrible packaging system where every tiny mistake can force a long long long rebuild.
They're obviously complicated because they're trying to offer a lot and e.g. Artix doesn't use selinux so there's one misery avoided straight away but it has a consequence.
IMO the core docs just don't prevent any of this confusion. They seem like a reference for people who already know what they're doing and enough tutorial for a very specific simple case that wasn't mine. People wouldn't bother to write their own tutorials if the docs filled the need.