Most of the time, sampling like this is just fumbling around and happy little accidents. There may be a goal they have in mind, but rarely would you know in advance what the end result should sound like exactly.
That's not exactly true. While there are plenty of happy accidents there's also plenty of times I've taken a sample and looped it knowing full well what it would sound like before I started.
Well, I said "most of the time", not "always". And that's talking from experience (both mine and that of fellow hobby musicians). It's true that sometimes you might come across a snippet and instantly know what you will be doing with it.
I'm talking from experience too. And from experience I found the opposite was true. Most of the time I found a snippet and knew what I was doing with it. Admittedly sometimes it sounded lousier than I'd expected and I thus scraped it but that's not really the same as having a sample and accidentally discovering it sounded good. Usually I'd pick a simple because I thought I could sound good (otherwise I wouldn't have bothered sampling it to begin with). So I think the term "happy accidents" is disingenuous because a lot of the time it wasn't an accident.
>So I think the term "happy accidents" is disingenuous.
I think, actually, that both of you are right. Everyone hears music differently, and some people may be better at putting together happy accidents, while others are better at hearing things beforehand. Ya know, just like the two of you. :)
Maybe now, but when Kid A was recorded hardware was a little more limited. So you'd spend a lot more time hunting for what sounded like good samples than you would ingest everything and see what sounded good.
These days it's pretty trivial to do the digital equivalent of "jamming with your band mates" when it comes to sampling but in the 90s you had to develop an ear for it because the process of capturing a sample through to cuing it in your tracker was longer and a lot more painful than what we take for granted now. And you often had to create all of your own samples, there weren't web sites you could download these things from like there are today. Even percussion needed to be sampled if you weren't lucky enough to own a drum machine.
One of the reasons I got into circuit bending in the latter end of my exploration in music was because I craved that instantaneousness with electronic music that I had when jamming with my guitar.
As for Kanye, I don't pretend to be an authority on his music but the few tracks of his I have heard haven't exactly been imaginative when it comes to sampling. He has taken tracks that were already good, taken the main riff from them and looped that. So I'd argue the creativity in his music is the lyrical content rather than his use of samples. Whereas you compare him to Daft Punk, Fatboy Slim or Prodigy and you can see that lyrical content is less important but the sampling is really creative, to the extent that the samples they've used are often unrecognisable from their original source.
edit: There's a YouTube video of Norman Cook (aka Fatboy Slim) talking about sampling using his Atari ST and how he'd hunt records for good sounding samples.