There are many reasons. But ultimately, it comes down to incentives. People who spend hours a day working with a flawed tool have incentives to find another. I

There are many reasons. But ultimately, it comes down to incentives. People who spend hours a day working with a flawed tool have incentives to find another. I had that experience myself using BackboneJS day in and day out for over a year. In my own time, I started exploring better alternatives such as AmpersandJS (which was very similar but handled subviews gracefully). After discovering React, I saw a further improvement beyond my then local maxima. People who lead products and hire engineers have incentives to choose something that will appeal to engineers who are looking for better ways to do things. It can both allow more hiring competitiveness at any given level of salary and filter out candidates who don't care about learning or finding cleaner solutions. People who create open source software have tremendous incentives to create something new and grow it. Even if it's not actually better than what it replaces, being the author of a popular framework carries tremendous career capital.