People in the west generally believe in a perfect form that all other forms are derived from. Starting from the bible with the perfect God who is part of all things, continuing with Plato's forms and being finalized in Kant whose logical gymnastics enshrined the idea in a way that has put it beyond reproach and criticism for many philosophers.

Nietzsche famously attacked this idea throughout most of his philosophy and later quantum physics came along and lent him a scientific backing. It proved that at the micro level the act of measuring something, simply our expectations of the event, affected the outcome.  
What this leaves us with is a universe which at the smallest level is a collaboration between our expectations and the laws of thermodynamics.

When judging the aesthetic value of an artwork we generally fall back on the idea of a perfect form, which to a certain extent derives from the human body. Note the obsession with anatomical correctness, even among cartoonists. Another example is the popularity of works that feature attractive people, which extends out of art and echos into advertising.

But as we well know these views of attractiveness are rarely canonized and change from year to year. The obese women of romantic era European painting give way to our modern twig like models and the Objet du désir of a multitude of subcultures such as the girls from our current favorite anime Madoka Magica. [link] It gets more complicated when you take into  account the fact that our media scape creates and warps our desires. Bow legs which used to be a point against Japanese girls are now the in thing after K-ON and it's stubby bow legged protagonists.

In a way this reflects or perhaps extrapolates in fractal form the idea of reality being a tension between perception and reality. We're attracted to works that project our own sub culture's beliefs and desires on to the human body.

So how do we judge art on aesthetic grounds when it originates from another subculture? How do we even judge our own art as it moves through phases?

The easy way they told us in art school is to judge it against it's own brief. How does the work fulfill it's own objectives? But what if the work's brief is completely retarded? As in the case of most of the work that institution produced. This would also preclude us from being able to laugh at the works of various deviant sub cultures on the web because hey maybe shitting dick nipples fit the brief all along.
We could just go with our gut feeling, making snap judgements without thinking about them which would be consistent with most dA users but then when it came to justifying our own work we'd be in trouble, especially if it didn't meet whatever criteria artworks have to meet on dA to become popular. And the above mechanisms would still be affecting our judgement on a subconscious level anyway.

At the end of the day most people go with popularity as a way to judge art. Visual art, music etc. With high art and hipsterdom things can go the other way, if something is popular it's common and more damningly it means the unwashed masses like it. As we all know a crowd can only agree on what the dumbest member of the crowd can understand. Take this idea forward a few steps and you have popular works are trash because they pander to the lowest common denominator.
A common hypocrisy I've noticed about the artists who adopt this idea is they shun a lot of work in galleries as too illustrative or populist, while listening to top 40 weekly hits like Justin Bieber.

With these considerations in mind I still can't figure if my work has gotten better or worse. It's certainly become less popular on the one hand, in fact if that's any indication of quality the assumption deriving from that would be that I had my voice to begin with and lost it. In terms of conforming to aesthetic ideals...it's bounced between animu characters to photo realistic urban landscapes to less photo realistic urban landscapes to animu characters.  Stylistically inconsistent would probably sum it up.

The fate of the artist is to toil at the altar of value.