A couple of days ago, I tried installing Debian on a machine I put put together from mostly spare parts and failed. I could not make X work because I have a video card that apparently is not supported. It did not recognize the NEC monitor. Also every few seconds it was claiming my timer/clock failed and was being reset. So I gave up and installed the official Red Hat 7.3 "Evaluation" 2-CDs w/o a hitch. All the hardware was recognized.
The video card, a Diamond Stealth 2000 3D with 2MB RAM, did not have a long product life and had problems working with earlier version of Red Hat as well, Indeed, the reason it was a "spare" was because I bought a VooDoo 3 card I knew was supported.
The CD drive, actually my wife's old CD burner which no longer burns CDs, I think reads OK and the Debian distribution (ver 2.2 rev 6) was on CDs burned by one of the local LUG members. So, there is chance the CDs were not reliably read.
Anyway, there are reasons not everyone runs Debian.