a user friendly user interface is one that the user is already familiar with. It is subjective, determined by the user, and will vary from user to user.

Think about the placement of face buttons for an xbox controller vs a ninttendo switch controller, specifically A and B. The function of menu accept is always on a, and menu back is always on b, but the physical placement of those buttons are opposite on the competing platform. Now think about a playstation controller, and where it puts menu accept and menu back. The glyphs are different, but a nintendo player will find it intuitive while the xbox player will be confused.