Glenn Havlicek climbed all the way up the ranks to managing director of global liquidity management, responsible for the issuance of all liabilities across the bank, over 22 years at J.P. Morgan and its predecessor firms, including Chemical Bank, in New York. He left the bank in 2005 and subsequently joined a London-based hedge fund started by former J.P. Morgan colleagues. Then in 2010, he became the co-founder/CEO at GLMX, a financial technology firm providing a money-markets trading, liquidity management and reporting platform with offices in New York, Palo Alto and London. For anyone thinking of quitting banking for fintech, Havlicek pinpoints the main issue: in fintech, your worries are existential. “When I worked at J.P. Morgan I had good days and I had bad days, and the good days are comparable to the good days I have at GLMX,” Havlicek says. “I had bad days at J.P. Morgan, but I always knew that when I woke up the next day, J.P. Morgan would still be there – when I had a bad day at GLMX, and there were plenty in the early days, I went to bed wondering if GLMX would still be there in the morning. “At a big institution, there is stress over the financial stability of a major company, but there is enormous infrastructure support, including HR, technology and financial backing, which gives you a long leash,” he adds. At J.P. Morgan, there are hundreds of thousands of people pulling in the same direction. It’s a lot different task to raise equity for a startup compared to raising the next few billions of dollars in fed funds at a huge bank. “At a small company, you can’t have too many bad days,” Havlicek says. “Many things must be done effectively, and you have to ask yourself, ‘What is the single thing I can be doing now to enhance the success of the company most?’ – that’s a very different mindset. “Being the CEO of an early-stage startup, you have to do everything – you have to learn to sell or you fail, which was an adjustment, even after I raised many trillions of dollars in the various markets at J.P. Morgan,” he says. “There are people who survive and thrive in that level of uncertainty and find it challenging and fun, which I do, and I have an enormous amount of respect for those who do, but some don’t.” Havlicek suggests quitting banking for a fintech company before you’ve got a financial cushion is a particularly bad idea: “I worked in banking for more than two decades to build a financial foundation for myself and my family before taking that personal career risk.” This article originally appeared in eFinancialCareers.