It’s all in the Design: an article by Ahmed Bouzid, Witlingo Founder and CEO,  that illustrates the difference between a skill that was designed for usability and skills that tackled the same thing (providing users with stock information) but that were not designed for high usability: https://www.linkedin.com/pulse/its-all-design-just-how-much-you-really-care-customer-ahmed-bouzid