What made me switch over was a lack of innovation in modelling tools in Modo and other established tools at the time and the lively ecosystem of addons in the Blender community, which innovated everywhere. I was particularly impressed by #hardops and wazou's pie menus, which I use to this day.
Despite the ongoing claims by many,, Blender has IMO the best UI in the business. EXTREMELY customizable, superb pie menus, almost vim-like shortcuts(incl 'pseudo motions' ).
Blenders UI is made for efficiency, which is what you want if you are serious about someting. Don't ever fall for the idea of 'artist friendly' UIs being ones with many buttons you can press. It will hold you back and slow you down. #gameart