I was just too lazy to switch until the past few months, where all that effort trying to work around the interface built up to the point where I got fed up. I didn't mind trying out a new way to do things, found shortcuts that helped my workflow, and definitely gave Unity a fair shake. I just found my ire building up, instead of what was promised to me which was an improvement that I might have to learn to appreciate. Sticking with it since its introduction, I just haven't found that promise to come true.
I switched to Mint at the tail end of 17.0 and have upgraded to 17.1, and it's been a pleasure, everything works the way I expect and there aren't any quirks. Tailoring the default install to what I wanted was intuitive, and didn't take very long at all (just disabling window snapping/tiling). The options aren't hidden away somewhere secret and are clearly labeled. I'm very happy. Granted, this is based on a history of working with KDE 2/3, Gnome 2, and prior to that the Windows interface, so I've been used to something similar the whole time I've been using GUIs. I don't know what someone with fresh eyes or born and bred into a world where smartphone interfaces are what you learn first would think of Unity. But for me, I'm extremely happy with Cinnamon and I'm pleased that with every new release they don't change the way things work.