by Mark Gleason

photo by Jornada Produtora

In an old comedy routine, Mel Brooks explained how you know when you’ve fallen out of favor at work: “You come into work one morning and your desk is on fire.”

All career changers seem to identify a specific moment when they knew their current jobs had passed their sell-by date. Here’s a sampling.

“Seven years before they dissolved my department, they started a new one that was full of people younger than those in my department. I had an inkling that we would teach the new group what we knew, and then they would cut us loose. I was right.” Bob Seymore, who moved from medical-equipment sales to a job as a nurse.

“When I was commuting into my office, I’d get off the train and see this herd of people who all looked like they hated where they were going. I thought, I can find another way.” Jason Harris, who after 10 years as a lawyer and six as a stockbroker, chose instead to sit at home in sweat pants and trade commodities online.

“I was in this big bank and one day I realized I was in the same place I was in 10 years earlier.” David Kelman, who left investment banking to open a Manhattan yoga studio.

“During my performance review, which was a tirade, I suggested maybe my boss didn’t want me in the job anymore. She reacted with complete relaxation, as if she’d been meditating.” John Harvey, who went from a big job at American Express to owning a local fish market.

Compiled by Alfred Gingold, a wide-ranging writer and blogger who has written a number of “Careers 2.0” profiles for WhatsNext.com.