There are two components to design or we should say creativity. The first component is to actually create something; draw, paint, dance, sing and so on and the other component is to evaluate the thing created to determine if it passes for something we wish to display to others. Both things require skill and both are subjective. Here’s what I have observed about both laymen and designers; they have trouble being really honest about their work. In terms of graphic arts some will opt for “good enough” rather than measure up to the level of professionalism exhibited in many publications and on consumer goods we purchase.
A singer must realize whether they can actually sing a listenable version of a song as opposed to just liking to sing. I like to put it this way: “appreciating talent in someone else is not the same as having it yourself.”
The key to doing great work is to be brutally honest about what you did and with courage doing whatever is necessary to fix it. Even if that means you have to leave it to more skillful hands.