Some people may debate me on the easy part, but it was easier that most free OS to install. I tried FreeBSD(or OpenBSD, it was a while ago) but quickly gave up when it wanted me to put in what Cylinder Head Sector to start the partition at and which CHS to end at. Slackware at the time needed you to tell it which CHS to start at, but also told you the first CHS that was free, then it would ask for the size of the partition, telling you the maximum size for the CHS you had chosen.
Linux took some thought, and a couple of tries as you had to leave room to create a swap drive, which it didn't tell you at first, but it gave you some hints about how big to make it after you had made your OS partition. It was vastly easier than BSD.
I had already had the fun of installing and using WinSock on Windows 3.11, so the Microsoft world had prepared me for the pains of setting up PPP and TCP/IP under Linux.
It may not have had the best coding, but it worked on most X86 computers that people had at the time. DOS with Windows was the only OS that was easier, and it wasn't much easier. Also DOS with Windows wasn't free. Timing is everything.
It was almost as easy to setup as the best paid product at the time. One it was working, you could easily download and use many productivity tools. Bash was familiar to Unix people, and anyone who had done any programming. X was pretty easy to get running, even it if was really hard to get running at the full resolution/colour depth of your video card.
It hit at the right time, was easy to setup, easy to install more software, and free.
Now it is easier to initially install than Windows. Where I find it lacking is that tweaking of the setup after installation that has lagged behind. Windows has the control panel. Each X windows manager has its own control panel which all seem to miss this or that feature. I'll admit, it has been a few years, so this may have improved, but Linux on the desktop just needs easy, graphical configuration tools for everything and it will be ready for everyone to use. Microsoft has given everyone else a window of opportunity with the debacle of where is this setting in Windows 8.x.