it needn't have an idea.
first it MUST have good quality, it's plain i think. idea is very good but photos without it aren't worse!
other options are specify I don't know do I looking at them.
It's only this first WOW

The idea, innovative idea is the
most important
point
then quality and
then wow...

the idea is important, but the quality of how the artist worked it out (for me things like lighting, textures, composition, angle (all in all technical execution) etc.) make a piece unique and worth faving imo.

Idea. I've read some fanfics that are, honestly *crap*, but the idea behind them is wow enough to bring be close to faveing it. I usually go for the wow factor, too.

A little late reply, but... where's the "Select all" option?
It must have a sensitive idea expressed in a eye-catching way, with the right tools.

I don't think that I could choose from just one. There's many reasons I'll fave a pic... It all depends on the piece in question I suppose.

idea and quality

I voted first impression must be a wow, but it's really more than that. It's complicated. Idea counts really much. And then there is quality, everyone can have brilliant ideas, but the good deviations are the ones that are well worked on(if ur not just really lucky; ). But if I can only pick one, it really matters much if ur awestruck when u see it.

You have to make me say "wow" but if you have a brilliantly innovative idea ie, smart title with an allegorical or symbolic representation in your piece, i would fav it also. if it's just an old idea with a new twist, or if it is well executed old idea, i'd also fav it. i think you do a very nice "wow" factor and your deviations are mostly well executed.

Das ist eine ziemlich schwierige Frage.
Natürlich muss der erste Eindruck gut sein, sonst würd ich mir das Bild gar nicht erst anschauen und auch Qualität (der Ausführung) ist ein Kriterium.
Aber würde man nur nach der Qualität gehen, würden Künstler mit weniger Erfahrung gar keine Favoriten abbekommen^^
Für mich sind deshalb die Emotionen, die das Bild erzeugt und die Idee dahinter am wichtigsten.