In her years as a probation officer north of Dallas, Patricia Lowell reckoned that she would work until age 65, confident that she could then retire halfway comfortably on her pension and Social Security. After retiring, she thought, she would pick up some extra spending money by working part-time retail jobs during the holiday season.

In that way, Lowell was like the three out of four Americans who say they plan to continue working after they retire from their main job.

But for Lowell, things did not turn out as planned. At age 58, she quit her job as a probation officer for Grayson County in order to care for her mother, who had cancer, diabetes and congestive heart failure. Her decision to leave her job of 23 years, she said, was made possible only by Texas’ then-recent decision to provide health insurance to longtime probation officers who retire before they qualify for Medicare at age 65.

"I wanted to continue working, but then this opportunity came up allowing me to retire and take care of my mother," Lowell said. "It all came together very nicely." She retired in late 2004, spending dozens of hours each week caring for her mother, who died in 2010 at age 92.

Now, nearly 10 years after leaving her job, Lowell is happily retired, with no plans to return to work. She is doing better financially than she anticipated, receiving her pension as well as $1,292 a month from Social Security. In an unexpected bonus, she remarried five years ago, and her husband’s retirement income has gone far to solidify their finances.

"I don’t regret at all that I retired," Lowell said. She is an active volunteer in her church, and she and her husband love taking road trips to explore Texas. And every few months they drive 300 miles south to Houston to visit her son and three grandchildren.

Lowell personifies a disconnect among Americans: While nearly three-fourths of Americans say they will continue working after retiring from their main job, only 18.9 percent of Americans age 65 or older actually remain in the work force. Many workers in their 40s, 50s and early 60s are convinced that they will want to or need to work well past 65 and even after retiring from their principal job, yet many retire earlier than they anticipated. There are many reasons for this: Perhaps they had health problems or grew unsatisfied with their jobs, or they realized that their nest egg was large enough for them to get by in retirement or, like Lowell, they needed to care for a loved one.

Sara Rix, an analyst at the AARP Public Policy Institute, sees numerous reasons so many Americans retire considerably earlier than they had anticipated. "A lot of people have expectations and desires to work in retirement, but the number who actually do is pretty low," Rix said. "A lot of things happen workers suffer ill health or job loss and that propels them out of the labor force."

Alicia H. Munnell, director of the Center for Retirement Research at Boston College, notes that many Americans are working until later in life. The percentage of Americans 65 and over who remain in the labor force has grown significantly to 18.9 percent from 12 percent two decades ago. Among the reasons she cites are people remaining healthier longer, fewer physically taxing lift-and-lug jobs, and, after the stock market plummeted during the recent recession, the conclusion that it is smart to work longer to build up one’s nest egg.

Munnell also puzzles over why most Americans say they want to work after retiring from their main job while a far lower percentage actually work after turning 65.

"Sometimes there’s a positive reason your spouse retires, and you decide you want to retire, too," Munnell said. She said there were numerous "shocks" that caused people to retire earlier than expected, like deteriorating health or an unanticipated change in wealth perhaps because of a soaring stock market. Another common "shock," she said, is a job change maybe a layoff or a transfer to a less satisfactory position or getting a new, more demanding, hotheaded boss.

"Sometimes people quit their main job and think they’re going to find another job," Munnell said. "But there’s still discrimination in the workplace. A lot of employers don’t like hiring old people that much. Older people look for work, but studies show that they then get discouraged pretty easily. You go, you look and then you give up."

That was definitely not the case for Hue Galloway, who worked for 12 years as a field technician for Ticketmaster in Connecticut. In that job, he crisscrossed the state, maintaining and repairing Ticketmaster’s computers and printers at dozens of establishments, from the Mohegan Sun casino to theaters in Hartford.

In 2008, during the depths of the recession, Galloway was laid off. He was 58 at the time. "I figured I’d be working there until 67 or 70," he said. "That’s what I was shooting for. I’d need the money. Plus, I enjoyed my job."

Galloway was determined to find another job; he spent three years looking, applying for more than 200 technical jobs. "I got no place," he said "I was like applying to five or six places a week, and over those three years, I might have gotten four interviews."

"I really feel I was discriminated against because of age," he added. "They found young people with two years of college to do basically the same kind of work I was doing, and they paid them less."

He was earning $17 an hour when he was laid off. For two years he lived on unemployment insurance and his savings, but that was not enough to keep the bank from foreclosing on his house. He could no longer afford the $1,500 monthly mortgage payments.

"It was very hard," he said. "But I just couldn’t pay for it." He is at least fortunate that his son lets him stay in one apartment of a three-family house that he rents out; in return, he serves as the informal superintendent.

In a survey of 1,502 Americans, AARP found that 31 percent of those who planned to continue working after retiring said they would do so because they "enjoy working." Thirty percent said they would continue "for extra money" and 21 percent "to have something interesting to do." Fourteen percent said they would continue working to be physically active and 11 percent to be mentally active. Ten percent said they would continue working to support themselves.

Many Americans think it won’t be hard to continue working into their late 60s or even their 70s. But Rix says it is not always so simple.

"Everyone is going to have to run faster and faster to stay in place at work, and that makes it more difficult for us to remain employed," she said. And once people leave their longtime jobs, she added, "In this economy, it’s pretty tough to find something else."

Teresa Ghilarducci, an economics professor and retirement expert at the New School, said many aging Americans underestimated the difficulties of continuing to work and overestimated the difficulties of retiring.

"People see the cost of not working isn’t so bad because they figure that they can get by," she said. "And the benefits of not working are much greater than they thought – they can relax a lot more."

Ghilarducci added that today’s jobs might not require as much lifting, bending and stooping as the manufacturing or warehouse jobs of old, but a lot of jobs are plenty demanding, requiring keen eyesight and intense concentration. "People thought their jobs would get a little easier, but they’ve gotten a bit worse," she said. "There’s a proletarianization of the jobs that older workers have."

Helen Dennis, an author and consultant on retirement and an adjunct professor at the University of Southern California, says it is not surprising that a far larger percentage of Americans say they are going to work into their late 60s and 70s than actually do.

"A big factor is uncertainly," she said. "People look at their savings and pensions and say, ‘I think it’s going to be OK, but I don’t know. I don’t understand the Affordable Care Act, and my mother is 90 and I have a daughter who just got divorced who is coming to live with me. There are so many uncertainties that to be safe I’m going to work until whatever age.’ But then when people reach 61, 62, 63, a lot of them figure out that they can retire."

Many Americans constantly weigh the pros and cons of continuing to work once they reach their late 50s and early 60s. Many conclude it’s not worth it. Dennis explained: "With the stresses of the workplace, with the mantra of doing more with less, now I’m doing two people’s jobs. We have a new manager. They’re changing the whole team again. The traffic here in LA is killing me, and my best friend just died and there’s a big message that life is short. I think that’s part of why people decide to retire."

She added, "Some people realize that any job I can find is for a minimum wage, and it’s not worth my time."

Dennis is pushing an idea called "Project Renewment" that seeks to help the nation’s first generation of career women plan for retirement. She says the hope is to make retirement more than "a return to the kitchen." "The whole piece is how to help career women face their next 20 or 30 years to find something you love to do and to give structure to the next chapter in one’s life," she said.

Barbara Goldberg is a prime example of this approach. For 30 years, she conducted focus groups for Fortune 500 companies including IBM, Coca-Cola, American Airlines and General Motors. Goldberg, 72, held regular salons at her Los Angeles home for, in her words, "intellectual and socially aware women." At one salon in 2008, a retired government official spoke about the problems facing drought-stricken countries in West Africa and the contaminated water that people drink there.

Within months, Goldberg closed her marketing firm and started a foundation to underwrite the drilling and construction of wells in Africa. The foundation, Wells Bring Hope, focuses on Niger and has raised nearly $2 million and financed 268 wells.

"I left my marketing work because I was so moved hearing about the dire need for water in West Africa and the plight of women and girls to get water," Goldberg said. "At the time, my business was slowing down, which was fine with me because I was traveling more and enjoying life a bit more. When this opportunity presented itself, it was the most natural thing in the world for me to do, although I had never worked in the nonprofit world."

Although economists would say she has technically retired because she no longer works for pay, Goldberg does not view herself as retired. She typically devotes 50 hours a week to raising money, holding meetings and speaking at elementary and high schools about Africa’s water woes.

"I loved doing focus groups, and doing that suited me just fine," Goldberg said. "But I was very conscious of what I wanted to do in the next chapter of my life. This is something that’s very meaningful to me, and it will leave a very powerful legacy to my three granddaughters."

Like Goldberg, Gary Westerman left his job voluntarily after three decades. He was an engineer and manager at a semiconductor company in Austin, Texas, and in the fall of 2012, his company announced plans to lay off 900 employees. "Two weeks before Christmas I volunteered to take the place of somebody else who had two or three kids," he said. "I could have stayed another four or five years. I have been through 37 rounds of layoffs in 33 years. I survived all of them."

Westerman, 65, is looking for another job, but it is proving harder than he anticipated. He is an adviser to several job clubs where he teaches people how to network better, because networking is such an important part of finding jobs.

"It will be another 10 years before I quit looking for jobs," he said.

Jerry Tollefson shares that sentiment, still reeling from leaving his job in November when the 500-bed nursing home in Milwaukee at which he worked announced it would close. For six years, Tollefson, 63, was its events coordinator, coaxing residents to tell stories of their youth, serenading them with Ella Fitzgerald and Perry Como records.

"I loved it," he said. "The nursing home gave me its above-and-beyond award."

"I can probably sneak by financially, maybe not taking all the trips you want to take," he said. "I can afford my home and have two squares a day."

He has been looking for jobs, but "the job market is difficult," he said. "Here in Milwaukee, probably like everywhere else, it seems that the jobs out there are geared to the IT computer business. When I get on a computer, I still hunt for the on-and-off switch. Young people who have grown up on computers, they have an advantage. Multitasking and being on the computer are not in my wheelhouse."

Still, Tollefson, who once did fundraising for nonprofits, is intent on finding a job. "The bottom line is, I get very antsy. I like to be busy," he said. "I want to work until 70. Maybe it’ll be part time."

A few days ago a nursing home invited him to interview for a position as its program and events assistant.

"It’s a nice fit, and hopefully something comes of it," he said. "Half the battle is having something you really enjoy doing."

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