What I wish I knew before I left Goldman Sachs at 35

York Zucchi used to work in investment banks. Between 1999 and 2007, he held a succession of roles at a succession of places, culminating in "strategic leads management" at Goldman Sachs. And since then? Since leaving Goldman Sachs and the finance industry aged 35? Zucchi's done 17 other things, none of them what we've come to expect of ex-corporate high achievers.

Zucchi's current job title is a case in point. He describes himself as, "Chief Coffee Drinker." And before that? "Dr. Frankenstein." And before that? "No Title Yet as I Have't Figured out My Role...."

Fundamentally, Zucchi is an entrepreneur - and quite a successful one. Unlike many bankers turned entrepreneurs, though, he doesn't take himself too seriously and is very frank about his mistakes.

"When I first came here [Zucchi's based in South Africa], I set up six business and five failed within nine months," he says. "The business that succeeded turned into a healthcare business which employed 1,800 people across Africa, but I embarked on ego-driven projects and didn't pay enough attention to cashflow and the board chucked me out...I've made a lot of money, but I've had a lot of bankruptcies."

Nowadays, Zucchi chairs two start-up funds run by the South African government and runs what he describes as a, "dating site for business." He also works with, "a lot of business school incubators and entrepreneurship clubs."

As such, Zucchi has unprecedented access to corporate employees who want to become entrepreneurs. His advice to most of them? "Don't."

"Everyone always imagines the grass is greener on the other side," says Zucchi. "Whether you're in an investment bank in Germany and you want to move to London, or whether you're in a corporate and you want to start your own business. But the reality is that you haven't experienced those pressures. You don't know what it's going to be like."

He says people are more romantic about entrepreneurialism than they used to be: "More people are saying that I won't have lifelong employment and job security in a large corporate, then I might as well become an entrepreneur."

Personally, Zucchi loves being an entrepreneur: compared to banking, he says it give him freedom and makes him feel properly alive. The flipside, is that it's "an emotional roller coaster."

"You have unbelievable days and you have shitty days," says Zucchi. "The grass isn't greener, it's different. When I screw up, I screw up because of things I've done. And when I succeed, I succeed because of things I've done, and I love it."

Zucchi says he left finance when he realised that he liked working on projects: "After a while you start to think why I can't I work on these projects on my own - and then you realize, you're an entrepreneur." Nonetheless,his time in finance helped make his entrepreneurialism possible: "The money came from my career in finance," says Zucchi, "I invested all my money in my own businesses, but the reality is that money only gets you so far and the more money you have the more you will spend."

To other financiers contemplating a life as a self-starter, Zucchi has this advice:

1. Start lean and mean. Be realistic - people aren't going to rush to fund you. Cash flow will not materialize as quickly as you'd hoped. You'll need savings or a partner with a salary so that you're not forced into a position where you're forfeiting your house.

2. Find a business that you know about already. Choose something close to something you've already done and learn about it by being a mentor and investor in an existing firm before you quit.

3. Be prepared for the unexpected - entrepreneurship never goes to plan. Start something and see what happens.

4. Don't quit. Try and start a business without leaving your corporate employer. See if you can cut your working time and take a pay cut rather than leaving entirely. "You're better off as an intrapreneur than an entrepreneur," says Zucchi. And that's the truth.

Contact: sbutcher@efinancialcareers.com