General :: Process Of Making A Distribution From Scratch ( Concerning Libraries, Etc. )?

I have C in a Nutshell but I'm learning Bash right now. I've gone through a lot of LFS, but didn't complete it. I'm still learning about symbolic links, hard links, libraries, and this sort of thing. I'm wondering about quite a few things at this point. How the hell can anyone make a distribution from the ground up? Even if they start with another distribution as a base, how do they know (I realize one person doesn't do all the work) what to do, what order to do it in, how to synchronize what they're doing with what everyone else is doing, etc. How do you know which software to compile and install first? etc.

Also, I'm entirely confused by this: how can everyone (even large teams) get everything working together? Knowing that this works with that and that doesn't work with this unless it's patched but that's what we're going with, etc. I can't understand how these things can be done without an almost unbelievable amount of effort unless a lot more is done by ./configure and make than I know about at this point.And I don't understand how libraries work at all. I mean, I'm going to learn a lot more and I've been reading a lot... but how can all the distributions just download and install 50 updates at a time and not have to restart the computer most of the time!? There are a hundred things happening in the background constantly. How does everything not just fall apart as soon as you update one package, let alone 50 at a time!? I realize this is stuff that you learn by reading, but I've been reading for quite a while now and I do not understand even the basics about why any of this works or how to know what works and what doesn't unless every single little piece of every distribution is gone over with a 50,000-page reference manual that's constantly updated. And all of this can't be as complex and hard to do as it seems, or there couldn't possibly be a hundred distributions that work and are updated constantly. Linux From Scratch is a good example. You have to download all the very specific versions of the software and patch it with special little patches, etc. How the hell can anyone keep track of all of this? Going by what I know about things, it's almost hard to believe that it's even done.