You know that a bad boss can cause you stress and anxiety. A bad boss can make you feel awful, but kill you? Yes. People who consider their bosses to be "unfair, arbitrary, inconsiderate, and generally deficient in managerial skills" are more likely to develop heart disease.

The logical thing to do when you're faced with a boss that is "unfair, arbitrary, inconsiderate, and generally deficient in managerial skills" is to find a new job. But, what if you are that boss?

Yes, the reality is, these horrible bosses are doing things that negatively affect their employees health. Granted, in the United States, people can quit a job whenever they want. Employment contracts are exceedingly rare and those that do exist certainly don't last for years and years. So, if you are one of these horrible bosses, your employees would quit, right? As long as they not, you're good.

Well, not quite. Every couple of weeks I get an email from someone that goes something like this: "I've been working for Company X for 10 years. My boss is mean and abusive and horrible. What can I do?" I always ask why the person has not moved on. I mean, logically, you'd think that when faced with a bad boss, you'd make every effort to get out. But people don't. For whatever reason, people stay with horrible bosses for years and years.

How can you make sure you aren't one of these horrible managers? Here's a list.

Be fair.

Easier said than done. You're human, and sometimes humans take a liking to one person and not to another. Because the law allows a manager to be a jerk as long as it's not based on race, gender, religion, or some other protected characteristic, managers think it's okay to be unfair. Of course, the thought is never, "I let Jane have three Christmases off in a row and have made Steve work all of them because I unfairly favor Jane." The thought is, "Jane deserves to have this. Steve doesn't." But if you couldn't articulate your reasons in a court of law (even though you won't have to, because it's legal to be an equal opportunity jerk), then you're not being fair.

Instead of judging people based on your feelings, use hard numbers. Make concrete goals and see how they measure up against them. If you can't justify a performance rating, a shift change or a project assignment based on hard facts, you're probably not being fair.

Be careful and considerate in your decisions.

One of the things that leads to heart disease is bosses who are arbitrary. Sometimes, managers--especially startup managers--want to have a fun environment. Culture means a lot. That's great. I'm in favor of great cultures. But that doesn't mean you should be whimsical. You need to not assign tasks because you ran into someone in the kitchen. You need to have policies and practices in place.

I received an email two days ago from a woman who wanted to know if she could fire someone for excessive absences. I said, "What's your absentee policy?" They didn't have one. She was flying by the seat of her pants. I said, "You need to call an employment lawyer and make a policy." Otherwise, you make arbitrary decisions, some of which can violate the law and land you in court.

Always be considerate.

A good manager is also a good leader. A good leader cares about the success of the people as well as the business. Be considerate. When someone gets the flu, don't hound them at home asking when they are going to get to this or that. When someone needs to leave early to take their car to the mechanic for a recall, say, "I hope it gets fixed quickly! See you tomorrow!" When someone struggles with a task, see if additional support and training will help.

Your business will do better when your employees know they can trust you to treat them like human beings. If you find yourself yelling and swearing, you're not being considerate.

Brush up on managerial skills.

Let's be honest, some startup founders have awesome ideas, but not a ton of practice managing people. While managing people is an art, there is a lot of skill that can go into it as well. Get yourself some training. Get your managers some training. Hire an executive coach if need be. Take a class. Don't just say, "I'm the boss. It's my company. I said so." It causes your employees stress when you stink.

If it's too difficult to remember these little things, remember this part of the big picture: Be nice. It's worth it. And it will keep you from killing your employees.