Good design is actually a lot harder to notice than poor design, because good designs fit our needs so well that the design is invisible.
A badly designed software will always lead to poor use by the end customer. What sets two similar services apart is always the user experience.
Using a bad designed application is a frustrating experience which wastes time, especially if the user is not familiar with the technology. That’s why it’s important to study the interaction between the user and the application to make it simple and intuitive as much as possible.