It's an unfortunate fact that more than 50% of working Americans admit to being unhappy on the job. And while some of that boils down to factors like money or work-related stress, a big part of it stems from the fact that many folks end up choosing the wrong profession. That's why it's important to understand not just what you want out of a job, but what you really don't want. With that in mind, here are some of the roles your Foolish investors would avoid at all costs.

Telemarketer

A smiling woman in an office setting wears a telephone headset.

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Selena Maranjian: What's the one job I wouldn't want? Well, that's a hard question to answer, as there are many jobs I don't want. I don't want to be a brain surgeon, for example, as I would be stressed out by the responsibility. I don't want to be a driver of trucks in a city, as I wouldn't want to have to get in and out of narrow streets and alleys. I wouldn't want to be a restaurant server, either, as I might worry too much about forgetting an order or dropping plates. Being America's president is unappealing, too, as there is just so much to the job and I don't feel sufficiently qualified.

So let me go with this job: telemarketer. Why wouldn't I want such a job? Well, it doesn't pay well, to start. According to the folks at Glassdoor.com, the national average salary is about $23,470. That's about $11 per hour if you work 40 hours per week. (Being a restaurant server also often pays little, but depending on where you work, you can hope for sizable tips, at least.) Next, think about what these poor folks have to do -- they're telemarketing -- or selling. And they're usually not selling something people are clamoring to buy; otherwise there would be little need to be calling people out of the blue. This kind of work means spending most of your working days getting hung up on and spoken to rudely by people who are not happy that you interrupted whatever they were doing. 

There's also some overlap between telemarketing and customer-service jobs, as many customer-service representatives are encouraged to upsell callers on additional services and products. Customer-service phone jobs might seem better, but there, too, you're often dealing with folks who have a problem, and many times it's one they're unhappy about -- which means they will take it out on the phone rep. Remember, too, that doing this job well require some skills that not everyone has. When people stay on the phone with you, you need to keep them there and successfully convince them to buy or try whatever you're pushing. Being an extrovert can help. Salesmanship isn't my best skill, so I think I will continue giving this job a wide berth.

Salesperson

A smiling man stands outside a house, clutching a clipboard.

IMAGE SOURCE: GETTY IMAGES.

Daniel B. Kline: Earlier in my career, almost a decade ago, I worked for my family ladder and scaffolding business. Part of my job involved managing a factory/rental/retail location, and part of it involved selling.

Once or twice a month I would go on the road, usually with our sales vice president, to call on clients. Selling existing customers was easy. In most cases, whether they ordered depended on what jobs they had, not my ability as a salesperson. 

The more difficult part of the job was cold calling. We, or sometimes just I, would show up at a potential customer's office without an appointment. Sometimes the person we dropped in on would be polite, and at other times we'd be treated like very unwanted guests. The rejections could be harsh, and the days we had a lot of cold calls were some of the rare days in my working life where I didn't want to get out of bed in the morning.

Selling wasn't a bad job, but it was incredibly difficult to get used to knocking on doors where your services and products could be harshly turned away. I was pretty good at selling, but getting psyched up to do it took a lot out of me.

There are people who take to sales and do it naturally. I was not one of those people, and I would not want to return to that world, but I have the utmost respect for people who can spend a career as a salesperson.

Teacher

Children raise their hands in a classroom as a teacher in the background points to the chalkboard.

IMAGE SOURCE: GETTY IMAGES.

Maurie Backman: Of all the jobs out there, I have to say that the one I'd probably be least happy with is being a teacher. Of course, I have tons of respect for educators, but I think it's the type of role I'm just not cut out to do.

One thing I really like about being a writer is the ability to perfect what I'm putting out there before actually doing so. If I write something and don't like the way it reads, I can edit or tweak it before submitting. As a teacher, however, you're always live, and you're always on. And given the audience, that's a lot of pressure.

Another thing is that I tend to prefer situations where I can work on my own schedule. From what I've seen, teachers have some of the least flexibility of all professions. Yes, they get summers off, and several breaks when school's not in session, but they can't easily take off without notice, and they certainly can't work from home when unplanned situations arise. At this point in my life, I need a job that offers much more flexibility.

Also, while I genuinely like children, working with kids means getting exposed to constant germs. A teacher friend of mine has told me that she's gotten sneezed and vomited on -- repeatedly -- throughout the years, and that it never really gets better. And then there are things like stomach viruses and lice, which children tend to be magnets for. As somewhat of a germophobe, I don't know how well I'd cope in an environment like that -- so I guess it's a good thing I don't work in a classroom.

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