Many seniors wind up working longer than expected, and often, it's not by choice. In fact, according to Northwestern Mutual's 2019 Planning & Progress Study, those who expect to work past the age of 65 out of necessity don't feel they have enough money saved to retire comfortably, are worried about Social Security, and fear the financial impact of rising costs such as healthcare.

For others, though, the decision to extend their careers doesn't boil down to financial issues, but rather a desire to keep working. In the aforementioned study, those choosing to work past age 65 are doing so for these reasons.

Smiling older man in business suit

IMAGE SOURCE: GETTY IMAGES.

1. "I enjoy my job/career and would like to continue"

The most common reason today's workers want to extend their careers is that they find their jobs fulfilling. If your job brings you joy, there's really no reason to give it up just because you're nearing retirement age. And if the hours are starting to get to you, talk to your employer about a phased retirement, where you gradually cut back your hours but get to continue working all the while.

2. "I want additional disposable income"

There's a difference between wanting more money in retirement and needing more money. For some people, working longer gives them the option to do the things they've always wanted to do, whether it's travel, own a boat, or finally join that country club. Therefore, think about your retirement savings and the lifestyle your money will buy you. You may have more than enough to cover the basics like housing, food, and transportation, but if you think you'll come up short on some of your other retirement goals, working longer could be your ticket to achieving them.

3. "It is a social outlet that will help me stay active/prevent boredom"

Retirement increases the likelihood of suffering from clinical depression by 40%, according to research from the Institute of Economic Affairs, and much of that boils down to boredom. Going from a full-time work schedule to no job at all is probably more difficult than you'd think, but if you don't occupy your time adequately in retirement, your physical and emotional health might suffer.

If you don't have a plan for how you'll spend your days in retirement, or don't have a lot of friends who have left the workforce, then it pays to think about extending your career. This especially holds true if going to work helps you maintain your physical health (for example, if you walk a lot in the course of your commute).

There's nothing wrong with closing out your career in your early to mid-60s if you can afford to do so. In fact, 65 is a relatively popular age to retire, because that's when coverage through Medicare kicks in. But even if you don't have to retire on the late side due to financial issues, there are several benefits to extending your career. Doing so could make it possible for you to have your dream retirement, not to mention spare you the mental anguish many seniors experience when they leave the workforce too soon.