There's a truism in design that goes something like "a user interface is primarily made for how its developers use it." In order to decide "most" you have to implicitly figure out who you are excluding. It's impossible to make something usable or understandable by "all". So, as with art, you have to know your audience. In most cases a dev is going to have the most success making things they would use themselves, for people who are of similar mind, or for whom the dev has genuine care for. Making something that one does not personally believe in it often seen as a cashgrab, phoned-in, corporatized, trend-following, selling out, slop, etc. This is easiest to see with accessibility features and whether it's a checkbox for funding or if the developer(s) actually care about people with disabilities using their stuff. But beyond that, really UX is part of design, and design is a type of art - not split from it. #aubreykunyap