Like AznHisoka said, there is a lots of apps that people need and want, but no one gives them attention, if you have a big company like Google, Apple .etc, you don't need something people want, you just put your name on it and it's sold. Just building something people want is not enough.
While it's true larger companies can get press on their products easier, if they're not building something people will pay for, it will flop. Take Apple's Ping for instance. Even Steve Job's magic couldn't make that cool.
To get your product out there and carry the WOM effect - your thing really needs to be something people crave and will pay for.
