It's perfectly simple, like many people here have said. The OS itself is very stable (apart from the early versions), but due to the unprotected memory and the open multitasking nature of the OS, it was very easy for a running application to trash system memory, thus causing a crash. The ST didn't really have that problem since it couldn't multitask that way, so naturally it'll feel more stable.
@commodorejohn
It's on Wikipedia, so it *must* be true
Workbench.library was only supplied on disk for the A4000T, since the ROM space was needed for a driver for the onboard SCSI. Every other kickstart ROM has had workbench.library included, meaning that once the boot flag was set on a floppy, or a hard drive was installed, you could boot. It wasn't much fun to use, but it was all there - GUI, DOS, mouse, sound etc.
