The critic's job is not simply to evaluate what's good or bad. It would be too boring to constantly declare, "This is bad" or "This is good." Besides, that burden of proof can be daunting. What mortal is free of self-doubt? Imagine an internal dialogue inside the critic's mind: Is it really bad, or is it that I missed the point? Am I upset or biased? Could I like this if I'd seen it under different circumstances? How do I know?These are important questions because they probe fundamental issues beyond the aesthetic realm.
In addition to evaluations of good and bad, you may enjoy a critic's skillful description of an installation (what the experts call ekphrasis). Take it as a sort of movie preview, something writer Giorgio Vasari regularly did for his readers in Renaissance Florence. A writer may go "historic" like J.J. Winckelmann (the purported father of art history) and inscribe the artwork within a broad context that derives implications by analogy. Or the critic can emulate Denis Diderot's technique of moral embroideries -- the kind of thing Arthur Danto achieved in his essay on Mapplethorpe's photography. Another approach is to analyze the artist's desires and obsessions, as Thomas Mann did with Dürer's Melancholia in his novel Doctor Faustus.
Baudelaire's attitude toward arts patrons amounted to an exercise in bad faith