It wasn't a 5 or even 15 minutes process. It involved anywhere from 5 to 25 floppies, you need to sit and watch (at least occasionally) at the screen to change the disks, of course disk #13, which you used just fine yesterday, now has an unreadable sector and not only you need to procure a replacement but the computer you [tried to] reinstall is now surely non-operational.
One day I managed to screw up Windows so it wouldn't start anymore. Luckily they were kind enough to include a copy of Windows on floppy disks. One of the disks (7/13?) had an error on it, and I never was able to reinstall Windows. Damn you, GDI.DLL. I know it was always GDI.DLL it would fail on because I probably tried to reinstall it ten times, hoping for a different outcome.
Back to DOS for me. At least I learned batch scripting...
For Windows 95, boot floppies were generally assumed to be needed (El Torito was only invented in late 1994), though the CD was usually used for the main installation.
For Windows 98, boot from CD was widely assumed to work at least on machines that came with it.