BANKSY breaks all the rules.
He is a vandal. He doesn’t commercialise his product- the outside art at least, which is free (obviously). He won’t reveal who he is. Need I go on?
You put these rule breaks together and what do you get? A global phenomenon.

It just goes to show that sometimes you need to turn things on their head and approach things from completely the opposite direction to convention. If Banksy (presumably a one-time art student) had taken a normal route to being promoted he’d have found an art dealer who would have assisted him for a big % of his income. The promoter would, no doubt, have put on a show or two, worked his/her connections and if Banksy’s art had been in the right place at the right time he might just have made it… maybe.
By taking his art onto the street he demanded attention – he didn’t ask if you wanted to see it, if you’re that way inclined (i.e. a gallery attendee)– he demanded you saw it. It had a huge amount of stand out, especially given what we are used to seeing on our streets – his work is inventive, clever and above-all very creative – most graffiti is done by vandals, not artists and is therefore, erm – rubbish. He benefited from “first mover advantage”– nobody had done this before, so he beat his contemporaries to market. Ultimately his approach was the epitome of guerrilla marketing. The lesson which marketers looking to do viral marketing is simple. It’ll only work if you’ve got compelling content and if you’re doing something different – there’s nothing worse than a thinly veiled, poorly executed viral piece… it’s a bit like your dad coming home one evening with an earring when he’s been an accountant for forty years, it doesn’t make him suddenly cool.
Banksy is now able to commercialise his work and has sold work for six figure sums, not bad for a Bristol vandal. He has now become conventional, in the sense that there a lot of people now doing the same as him (see link at the end of this post), so it will be interesting whether he changes his approach. I really wouldn’t be surprised if he turned the art world on its head and completely reinvented himself. That’s the trouble when your brand is all about being unconventional – if you are successful it’s pretty hard to stay unconventional.
Bristol Street Art catalogues the street art in Bristol (I didn’t realise how worryingly similar my site looks to theirs – complete coincidence!) Have a gander.