A hard lesson can be that economic accessibility is crucial to creating demand. Here lies the first rule of marketing. #1 Price it right. Rule #2 Locate your audience. I know it sounds like selling real estate! Shocking!!
These simple facts exist whether the artist is dealing with the public galleries and international biennale exhibitions industry, or the commercial galleries and auction houses. Only the naive believe that if the art is 'good' it will sell, and if not, it won't. Again we know from art history books that this is just not correct.
No, the art will not speak for itself....unless it is put out there. Through connections and networking, an artist can find an audience. Lucky is the artist who is "discovered" by an admiring agent with good connections who deems his art "important". It is really no more important than another, but the agent/dealer has an investment to promote and so, like the stock market, drums up buyer investors. For the artist in this kind of deal, however, the increased demand insists on supply, and to the the tastes of the buyer. This can be at odds with the creative nature of the artist who would like time to pursue an aesthetic outside what is now expected due to marketing and increased demand.