When we think about summer jobs, we tend to imagine casual, daytime positions that leave us with a little pocket cash and maybe a nice, glowing tan to boot. But the summer job I held before my senior year of college was nothing like that. Rather, I was cooped up in an investment bank office working 80 hours a week or more. It was the most grueling, intense work experience of my life, and here's what I learned from it.

1. A little short-term sacrifice is worth it

It wasn't easy working from 8:00AM until midnight most days while my friends were clocking in four-hour shifts a day at their summer gigs and spending their nights having fun. But because my company paid me by the hour, and it was a job at which I was eligible for overtime, I wound up making a small fortune that summer -- enough to pay for my entire senior year of college without having to take out additional loans. Even when I found myself longing for a free night, or a few hours of extra sleep, I would power through at the office knowing that my hard work was going to have a positive financial impact after the fact.

Woman at a computer in a dark office

Image source: Getty Images.

2. Long hours are bearable when you enjoy your work

Let's be clear: I could never spend 16 hours a day doing something I hated. Thankfully, the work I did that summer was interesting and exciting. I learned a ton about evaluating businesses, analyzing data, and other such financial tidbits that broadened my knowledge base. Therefore, while I often felt the strain of working so many hours, the silver lining was that I was rarely, if ever, bored.

3. Supportive colleagues are everything

I know a lot of people who can't stand their coworkers and find them annoying and unbearable. But that wasn't my experience that summer. I worked with people who ranged from age 18 all the way up to their 60s (and possibly 70s -- it was hard to tell, and I certainly wasn't asking), and the overwhelming majority of those people were smart, supportive individuals with great personalities and a similar work ethic to mine. Having great colleagues certainly made it more pleasant to spend my days -- and nights -- locked away in an office.

4. I could never do this on a long-term basis

I'm extremely grateful that I got the opportunity to work at a respectable company, earn lots of money for someone my age, and have an impressive gig to put on my resume. And I don't regret sacrificing that summer for all of those things one bit. At the same time, I realized back then that I could never maintain that sort of schedule indefinitely. The one thing that prevented me from burning out that summer was knowing that the role was temporarily, and that come late August, I'd be back in school taking classes, working a couple of part-time jobs, and essentially regaining my freedom.

In recent years, I've taken even more steps to achieve a better work-life balance, which is something so many people I know continue to lack. It's good to push yourself on a short-term basis if it helps your career and your finances (or both simultaneously), but at the end of the day, even if you love what you do, there comes a point when you need to be a person as well. And that's perhaps the most important thing I learned that summer.

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