What is a masterpiece?

We speak of course of “masterpieces”, of art one must have seen, the “canon” of art. But how do we measure the quality of art?

Fact is, that the quality criteria have changed again and again over the centuries.

For a long time, it was the technical skill, the masterly brushstroke, for example, or the detailed silverwork. The artistic inspiration, the “idea” is also a criterion; or the groundbreaking innovation, as well as-not only in modern times- the breaking of convention.

And who decides on the mastery of a work? Art historians? The art market? The art critics in the magazines? Or even you, with your very subjective judgment of taste? In your opinion, what turns a work of art into a masterpiece?