All more often products and services are found in a digital form. Regardless the form, it's wise to keep the user satisfied, if not even in a good mood. Therefore, user intefaces should_at_least be laid open to the eyes of an experienced UX-specialist, before they are let out on the market.
User interface (UI) solutions can be analysed in a quantitative or qualitative way. Big projects rely mainly on the outcome of quantitative research, whereas in smaller projects a qualified specialist analyses can produce significant and whole sufficient a gain.