I am a programmer so my own approach is to find whatever similar project had to solve the same UUx requirements, either by searching the web or from memory, and to start iterating on that. Fortunately it is pretty uncommon to have to reinvent the wheel.
Well, most of the UX designer I have worked with don’t do that, and most didn’t seem to have that much experience using softwares. I have seen some weird shit in meetings, as the “non-expert” it can be very delicate to call those bad designs repeatedly. Even basic rules like when to use radio buttons vs checkboxes are sometime broken. All people working 6 figure jobs++.
I guess I have spent too much time on the computer over the last 2 decades and played around with too many interfaces to ever be satisfied with much of anything.