My first, charmed week as a student at Harvard Business School, late in the summer of 2001, felt like a halcyon time for capitalism. AOL Time Warner, Yahoo and Napster were benevolently connecting the world. Enron and WorldCom were bringing innovation to hidebound industries. President George W. Bush — an H.B.S. graduate himself — had promised to deliver progress and prosperity with businesslike efficiency.

The next few years would prove how little we (and Washington and much of corporate America) really understood about the economy and the world. But at the time, for the 895 first-years preparing ourselves for business moguldom, what really excited us was our good luck. A Harvard M.B.A. seemed like a winning lottery ticket, a gilded highway to world-changing influence, fantastic wealth and — if those self-satisfied portraits that lined the hallways were any indication — a lifetime of deeply meaningful work.

So it came as a bit of a shock, when I attended my 15th reunion last summer, to learn how many of my former classmates weren’t overjoyed by their professional lives — in fact, they were miserable. I heard about one fellow alum who had run a large hedge fund until being sued by investors (who also happened to be the fund manager’s relatives). Another person had risen to a senior role inside one of the nation’s most prestigious companies before being savagely pushed out by corporate politics. Another had learned in the maternity ward that her firm was being stolen by a conniving partner.

[Housecleaners, nannies, health aides and domestic workers are organizing to secure job security. Read about the new labor movement in our Future of Work issue.]

Those were extreme examples, of course. Most of us were living relatively normal, basically content lives. But even among my more sanguine classmates, there was a lingering sense of professional disappointment. They talked about missed promotions, disaffected children and billable hours in divorce court. They complained about jobs that were unfulfilling, tedious or just plain bad. One classmate described having to invest $5 million a day — which didn’t sound terrible, until he explained that if he put only $4 million to work on Monday, he had to scramble to place $6 million on Tuesday, and his co-workers were constantly undermining one another in search of the next promotion. It was insanely stressful work, done among people he didn’t particularly like. He earned about $1.2 million a year and hated going to the office.

“I feel like I’m wasting my life,” he told me. “When I die, is anyone going to care that I earned an extra percentage point of return? My work feels totally meaningless.” He recognized the incredible privilege of his pay and status, but his anguish seemed genuine. “If you spend 12 hours a day doing work you hate, at some point it doesn’t matter what your paycheck says,” he told me. There’s no magic salary at which a bad job becomes good. He had received an offer at a start-up, and he would have loved to take it, but it paid half as much, and he felt locked into a lifestyle that made this pay cut impossible. “My wife laughed when I told her about it,” he said.

‘When I die, is anyone going to care that I earned an extra percentage point of return? My work feels totally meaningless.’

After our reunion, I wondered if my Harvard class — or even just my own friends there — were an anomaly. So I began looking for data about the nation’s professional psyche. What I found was that my classmates were hardly unique in their dissatisfaction; even in a boom economy, a surprising portion of Americans are professionally miserable right now. In the mid-1980s, roughly 61 percent of workers told pollsters they were satisfied with their jobs. Since then, that number has declined substantially, hovering around half; the low point was in 2010, when only 43 percent of workers were satisfied, according to data collected by the Conference Board, a nonprofit research organization. The rest said they were unhappy, or at best neutral, about how they spent the bulk of their days. Even among professionals given to lofty self-images, like those in medicine and law, other studies have noted a rise in discontent. Why? Based on my own conversations with classmates and the research I began reviewing, the answer comes down to oppressive hours, political infighting, increased competition sparked by globalization, an “always-on culture” bred by the internet — but also something that’s hard for these professionals to put their finger on, an underlying sense that their work isn’t worth the grueling effort they’re putting into it.

This wave of dissatisfaction is especially perverse because corporations now have access to decades of scientific research about how to make jobs better. “We have so much evidence about what people need,” says Adam Grant, a professor of management and psychology at the University of Pennsylvania (and a contributing opinion writer at The Times). Basic financial security, of course, is critical — as is a sense that your job won’t disappear unexpectedly. What’s interesting, however, is that once you can provide financially for yourself and your family, according to studies, additional salary and benefits don’t reliably contribute to worker satisfaction. Much more important are things like whether a job provides a sense of autonomy — the ability to control your time and the authority to act on your unique expertise. People want to work alongside others whom they respect (and, optimally, enjoy spending time with) and who seem to respect them in return.

And finally, workers want to feel that their labors are meaningful. “You don’t have to be curing cancer,” says Barry Schwartz, a visiting professor of management at the University of California, Berkeley. We want to feel that we’re making the world better, even if it’s as small a matter as helping a shopper find the right product at the grocery store. “You can be a salesperson, or a toll collector, but if you see your goal as solving people’s problems, then each day presents 100 opportunities to improve someone’s life, and your satisfaction increases dramatically,” Schwartz says.

One of the more significant examples of how meaningfulness influences job satisfaction comes from a study published in 2001. Two researchers — Amy Wrzesniewski of Yale and Jane Dutton, now a distinguished emeritus professor at the University of Michigan — wanted to figure out why particular janitors at a large hospital were so much more enthusiastic than others. So they began conducting interviews and found that, by design and habit, some members of the janitorial staff saw their jobs not as just tidying up but as a form of healing. One woman, for instance, mopped rooms inside a brain-injury unit where many residents were comatose. The woman’s duties were basic: change bedpans, pick up trash. But she also sometimes took the initiative to swap around the pictures on the walls, because she believed a subtle stimulation change in the unconscious patients’ environment might speed their recovery. She talked to other convalescents about their lives. “I enjoy entertaining the patients,” she told the researchers. “That is not really part of my job description, but I like putting on a show for them.” She would dance around, tell jokes to families sitting vigil at bedsides, try to cheer up or distract everyone from the pain and uncertainty that otherwise surrounded them. In a 2003 study led by the researchers, another custodian described cleaning the same room two times in order to ease the mind of a stressed-out father.

To some, the moral might seem obvious: If you see your job as healing the sick, rather than just swabbing up messes, you’re likely to have a deeper sense of purpose whenever you grab the mop. But what’s remarkable is how few workplaces seem to have internalized this simple lesson. “There are so many jobs where people feel like what they do is relatively meaningless,” Wrzesniewski says. “Even for well-paid positions, or jobs where you assume workers feel a sense of meaning, people feel like what they’re doing doesn’t matter.” That’s certainly true for my miserable classmate earning $1.2 million a year. Even though, in theory, the investments he makes each day help fund pensions — and thus the lives of retirees — it’s pretty hard to see that altruism from his window office in a Manhattan skyscraper. “It’s just numbers on a screen to me,” he told me. “I’ve never met a retiree who enjoyed a vacation because of what I do. It’s so theoretical it hardly seems real.”

There is a raging debate — on newspaper pages, inside Silicon Valley, among presidential hopefuls — as to what constitutes a “good job.” I’m an investigative business reporter, and so I have a strange perspective on this question. When I speak to employees at a company, it’s usually because something has gone wrong. My stock-in-trade are sources who feel their employers are acting unethically or ignoring sound advice. The workers who speak to me are willing to describe both the good and the bad in the places where they work, in the hope that we will all benefit from their insights.

The smoothest life paths sometimes fail to teach us about what really brings us satisfaction day to day.

What’s interesting to me, though, is that these workers usually don’t come across as unhappy. When they agree to talk to a journalist — to share confidential documents or help readers understand how things went awry — it’s not because they hate their employers or are overwhelmingly disgruntled. They often seem to love their jobs and admire the companies they work for. They admire them enough, in fact, to want to help them improve. They are engaged and content. They believe what they are doing matters — both in coming to work every day and in blowing the whistle on problems they see.

Do these people have “good jobs”? Are they luckier or less fortunate than my $1.2 million friend, who couldn’t care less about his firm? Are Google employees who work 60 hours a week but who can eat many of their meals (or freeze their eggs) on the company’s dime more satisfied than a start-up founder in Des Moines who cleans the office herself but sees her dream become reality?

As the airwaves heat up in anticipation of the 2020 election, Americans are likely to hear a lot of competing views about what a “good job” entails. Some will celebrate billionaires as examples of this nation’s greatness, while others will pillory them as evidence of an economy gone astray. Through all of that, it’s worth keeping in mind that the concept of a “good job” is inherently complicated, because ultimately it’s a conversation about what we value, whether individually or collectively. Even for Americans who live frighteningly close to the bone, like the janitors studied by Wrzesniewski and Dutton, a job is usually more than just a means to a paycheck. It’s a source of purpose and meaning, a place in the world.

There’s a possibility, when it comes to understanding good jobs, that we have it all wrong. When I was speaking to my H.B.S. classmates, one of them reminded me about some people at our reunion who seemed wholly unmiserable — who seemed, somewhat to their own surprise, to have wound up with jobs that were both financially and emotionally rewarding. I knew of one person who had become a prominent venture capitalist; another friend had started a retail empire that expanded to five states; yet another was selling goods all over the world. There were some who had become investors running their own funds.

And many of them had something in common: They tended to be the also-rans of the class, the ones who failed to get the jobs they wanted when they graduated. They had been passed over by McKinsey & Company and Google, Goldman Sachs and Apple, the big venture-capital firms and prestigious investment houses. Instead, they were forced to scramble for work — and thus to grapple, earlier in their careers, with the trade-offs that life inevitably demands. These late bloomers seemed to have learned the lessons about workplace meaning preached by people like Barry Schwartz. It wasn’t that their workplaces were enlightened or (as far as I could tell) that H.B.S. had taught them anything special. Rather, they had learned from their own setbacks. And often they wound up richer, more powerful and more content than everyone else.

That’s not to wish genuine hardship on any American worker, given that a setback for a poor or working-class person can lead to bankruptcy, hunger or worse. But for those who do find themselves miserable at work, it’s an important reminder that the smoothest life paths sometimes fail to teach us about what really brings us satisfaction day to day. A core goal of capitalism is evaluating and putting a price on risk. In our professional lives, we hedge against misfortune by taking out insurance policies in the form of fancy degrees, saving against rainy days by pursuing careers that promise stability. Nowadays, however, stability is increasingly scarce, and risk is harder to measure. Many of our insurance policies have turned out to be worth as much as Enron.

“I’m jealous of everyone who had the balls to do something that made them happy,” my $1.2 million friend told me. “It seemed like too big a risk for me to take when we were at school.” But as one of the also-rans myself — I applied to McKinsey, to private-equity firms and to a real estate conglomerate and was rejected by them all — I didn’t need any courage in making the decision to go into the modest-paying (by H.B.S. standards) field of journalism. Some of my classmates thought I was making a huge mistake by ignoring all the doors H.B.S. had opened for me in high finance and Silicon Valley. What they didn’t know was that those doors, in fact, had stayed shut — and that as a result, I was saved from the temptation of easy riches. I’ve been thankful ever since, grateful that my bad luck made it easier to choose a profession that I’ve loved. Finding meaning, whether as a banker or a janitor, is difficult work. Usually life, rather than a business-school classroom, is the place to learn how to do it.