User Experience or UX it the part where designers piece together how a product should work. This is best done after the User Research stage is done. The design will be based on the research. This allows the UX Designer to produce a design that works best for the end-users and for the business making the product more valuable to both.
Putting users at the centre of your business means you learn and adapt to their needs. This helps users get what they want from you and in turn, helps your business.