When?

When do you launch? / When do you act? / When do you change? It just might be the most important question an entrepreneur ever answers.

- By Jim McKelvey / Cofounder of Square

I AM AN ENTREPRENEUR, but I am also a glassblower— AND EVERY GLASSBLOWER HAS A MENTOR.

In fact, we all have the same one: Lino Tagliapietra. Glassblowing is the only profession I know where everyone agrees on who the best practitioner is. Nobody knows who the best accountant or mortician or loan shark is, but the world’s best glassblower is Lino.

Everyone learns from the Maestro, usually by meeting someone who has met someone who has taken one of Lino’s classes. Maestro’s classes are legendary, right down to an admission process that would impress the Harvard registrar. There was even an essay question, and a collection of T-shirts for sale to salve the pain of rejection. It took me 15 years to earn a place, but I was finally admitted.

Lino’s class lasted two weeks, and during that time, each student was allowed to ask Maestro one question. Everyone obsessed over his or her question, and as a result, most questions followed the same format: A student would ask Lino how to do something impossible with glass. We would then sit in rapture as Maestro demonstrated how to do it. But when the day came for my question, none of the other students even paid attention to Lino’s answer, for my question was so basic that they already knew it. Or so they thought.

I asked the best glassblower in the world how to put a simple foot on a bowl.