Because it's from Microsoft and they are EVIL! Seriously though, I've worked on projects with Angular and Backbone and have messed around with React, but every

Because it's from Microsoft and they are EVIL! Seriously though, I've worked on projects with Angular and Backbone and have messed around with React, but every project both big and small that I have started has ended up using KnockoutJS. It is easy to learn, performs amazingly well even with tens of thousands of records, has extremely powerful custom bindings to extend its functionality and even has excellent templating to boot! Of course in the end people (including myself) just go with what they know and/or want to learn - so which JS framework is "the best" is just a matter of opinion. Having said that, I'd love to hear from someone that has years of Knockout experience explain why they think it is inferior to any other library OR framework.