If I was young wasn't married with kid, I would have loved to go and be an apprentice to an old master. I couldn't imagine anything more rewarding and terrifying at the same time.
I can imagine a master saying something like "to start, you will wedge clay for a year".
I watched a show I really loved, a documentary called, "Jiro Dreams of Sushi". It is a fantastic documentary about a master sushi chef, who makes his apprentices cook rice for the first 2-5 years or something. I can't remember it now since I watched it so long ago, but it was a rather long time to make nothing but rice. They all made rice that long because to be trained under this master was a great accomplishment.
In this documentary, people say when Jiro dies, there never will be as good of sushi in the world again. I think when people can make this kind of statement about your work, you can be considered a master.
A lot of people equate master to years in the field. Where in truth the years you do something only mean as much as you attempt to accomplish in those years. If you make the same mug you made in year 2 of your career at year 30 with no real improvements, I wouldn't really say your a master at making mugs.
@ DirtRoads: The story about the self proclaimed master coming into your studio is hilarious.
Edit: It is interesting to think about how much we move around in our fields. It would be a good discussion to have about how narrow one could focus their work on. Could you narrow your work down to only certain forms? Down to firing only? Down to testing glazes only? I mean how far can you go down a narrow path. It would be interesting to be a potter who only made one form, but then how do you glaze that form? Do you only use so many glazes and continue to improve those glazes forever? So all your work looks the same forever. It's a tricky thing in pottery to figure out.
I could see oneself focusing on the form they enjoy the most and never changing out of that form. I mean you could spend a lifetime making the best mug ever. Have forms based on gender, how one holds a mug, hand size, finger size, what type of lip you think is best. Think about what you could charge for a mug if you became known as one of the best mug makers in the world. People could custom order their mugs to fit their hands and fingers exactly how they wanted. This sort of reminds me of my bison tools I ordered. He had me measure my hands for the tools, and man they fit nice.
You could figure the best clay for microwaves and thermal test for clay & thickness to hold temperatures the longest without being too thick, you could figure out glazes that are the best resistant to coffee and tea stains. Hell I could go on and on with ideas on what you could gain from mastering one form, and to think about that makes me think that is near impossible to become a master without a complete lifetime in the field always striving for improvement and never settling.