What's more important in an essay: quality or word count?

Quality always wins...however, if a professor says 2,000 words and you have 1/2 of that, then you have not met the requirements. Most likely, you fell victim to what most writers mistakenly do - you TOLD instead of SHOWED. Have someone who is not familiar with your topic AT ALL read it over & explain back to you what they think you were trying to say. Most people do not add enough detail because they write for their teacher/professor and assume that the reader understands all references and comments. You should always write for someone who is not familiar with the subject and therefore fully explain details and give very vivid, detailed explanations and examples. When your friend tells you what the essay means, stop and note anytime the reader gets it wrong or says, "I'm not really sure..."

Both are important, but in this case, the word count. You should write more. To be honest, the quotes don't count in the word count for most classes (I asked my prof, you should ask yours) so your essay is a little TOO short. If you don't reach the required word count, the prof may even deduct marks on it.

Since most professors only bother to read the beginning paragraph and decide the overall grade on that, quality is most important at that part of the essay, and the rest of the essay can be full of BS.

quality but you'll probably lose marks for inability to meet the world count your prof gave.

Put it this way, I have walked the same walk for 3 years now do you get it!