Xavier H. answered 02/12/20
Professional Art Tutoring
I think there is a line between personal preference and objectivity when it comes to art. We can measure the value of an artwork, objectively, in many ways. We can consider the amount of skill required to execute. We can consider the artist's intent and how well or not well they communicated this.
An artist credibility generally comes from their understanding of the process. An artist has a refined sensibility, just as any other professional in any other craft, and can more comfortably assess the artwork. Maybe an artist realizes that the extreme variety of strokes within a painting is indicating that a long period of time has passed over the course of the work, or maybe that there was more than just one individual painter.
In the end, don't allow anyone to tell you your opinion is wrong as a viewer. The artist's job is to communicate. Not everyone will like what they've made, but that shouldn't be the goal for ANY artist. The goal is to communicate.