Failures that were ahead of their time. some were just not marketed and some were over priced.

http://listverse.com/2013/01/12/10-innovative-pieces-of-technology-that-failed-miserably/
http://www.pcmag.com/article2/0,2817,2325931,00.asp
http://www.businessinsider.com/startup-failures-2011-5

Underfunded and facing a Monopolistic opponent.

https://fee.org/articles/the-tucker-car-did-the-big-guys-do-it-in/

Just saying the best doesn't always get adopted, it's a shame really but most people lack the drive to research anything and just use whats easy and what everyone else is using.