Your first ‘real’ job should give you the foundation needed for future success. This couldn’t have been more true in my case, but not in the ways you’d expect.

After graduating from the UC Berkeley Haas School of Business, I went to work as an analyst in the technology group of a bulge bracket investment bank. It paid very well and was in the tech field I wanted. This was it. I was on my way.

It was 2002, during the depths of the dot-com bust and when the tech sector was a wasteland. I was working with the only active client for the group, a private technology company that engaged our bank to sell itself. As this was the only business for the group at that time, this deal was under tremendous scrutiny on all levels.

I was working 100-plus hour weeks for three straight months, and I remember vividly one weekend when I had a horrible flu. I was at the office working on a Saturday when the VP managing this deal went out to dinner. As she left, she asked for “another rev” on the presentation. Translation: I had to put in another eight hours that night, with a fever, and the CEO wanted to review the presentation on a 7:00 call the next morning (Sunday).

I can’t remember the exact mixture of caffeine and decongestants I took, but I somehow managed to get the presentation done, nab a couple hours of sleep and arrive back in the office for the call. I was drowsy, achy and coughing miserably during the call. At one point the VP muted the phone, looked at me and said, “I’m going to need you to perk up.”

Perk up I did, but not in the way she was thinking. At that precise moment, I knew I was in the wrong job and more importantly, the wrong career path. In one life lesson she had unwittingly (and unrelentingly) taught me three key things:

• Pursue great people and not the paycheck
• Do work you love
• Create a healthy work-life balance

Suddenly, the income was not as important as being able to work with great mentors and people I could learn from. I had hoped for this when accepting the investment-banking job and soon realized it didn’t exist. I remained blinded by the pay until that mute button was pressed. I left and ultimately took a job that paid much less but was far more rewarding in terms of the people and the work.

Having a clear understanding of what was important to me was critical not just when co-founding a company that I wanted to work at – but also to create a place that fosters satisfying careers for all those I work with as well.

Read all answers to the 40 under 40 Insider question: What are 3 must-have skills to land your first job?

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