Quicken had 46 direct competitors the day it launched, many of which had 3x as many features. By all appearances of the times, it was a terrible investment, yet it disrupted the industry. Its #1 differentiator? An "Intuit"ive design.
Mike Gebbia credits UX for turning Airbnb from a failing company into one with a $10B evaluation.
In year 1, Jeff Bezos invested 100x more into customer experience than advertising.
On a shoestring budget, Apple invented an entirely new industry (personal computing), simply by making an existing product easier to use.
It wasn't an enterprise or angel investor that ended the Myspace era, it was an unsuspected college kid sitting in his dorm room, theorizing what people really wanted was a simpler way to connect online.
Google was user testing and adapting to users' needs long before they published a single line of code. Since then, well... you know.