This is because in our society innovation is profit driven and there's simply not much profit to be made by solving the world's most urgent problems.

Why cure cancer when you can make 1,000x more money creating the next generation of boner pills?

Why create more sustainable energy efficient electronics when you can make 1,000x more money figuring out how to squeeze an IMAX camera into an iPhone so people can post photo-shoots of themselves online and pretend they're celebrities?