About a decade ago, I described a phenomenon I called "CEO Disease" as follows: "a progressive illness that causes the sphincter to enlarge until it covers the entire body, causing excess irritation that can only be relieved through frequent underling osculation."

While I was exaggerating (but not by much), I based the definition on in-depth interview of top CEOs, most of them in high tech. Despite the large number of the CEOs I've met, I can count the number I'd want as a close friend on the fingers of one hand, and I'd still have three fingers left.

Based on my observations, here are the five reasons CEOs turn into jerks along with some suggestions for would-be CEOs who'd rather not become a victim of CEO disease:

1. Exhaustion

Partly because they tend to love their jobs and partly because they're trying to be role models (and extract the maximum amount of work from other employees), many CEOs work extremely long hours. As a result, most CEOs don't get enough sleep and, as their exhaustion grows, they become increasing testy. Because there's nobody to tell them to STFU, they start relieving their stress by dumping on everyone else.

My suggestion: Stop thinking of "down time" as an expenditure of time that could be better spent working. Instead, think of "down time" as an investment of time that will ultimately make you more effective and better able to succeed because you won't constantly be alienating your best employees.

2. Insecurity

Let's not kid ourselves. Being CEO is a terrifically difficult job at ALL stages of a company's growth. In a startup, the CEO must do just about everything and then, as it grows, must learn to delegate while simultaneously "upping their game" and learn new skills. Because of this, every CEO is "winging it" to some extent and it would be very strange indeed if they didn't sometimes feel as if they're not up to the job.

My suggestion: The best way to overcome insecurity is to publicly admit and "own" your own ignorance. One of the smartest (and least jerky) CEOs I ever met once told me: "My job is managing the white spaces in between the boxes on the org chart." He was owning his ignorance... and it made him a stronger leader.

3. Grandiosity

Grandiosity isn't the opposite of insecurity; it's the flip side. The more insecure a person is on the inside, the more grandiose they are on the outside. Indeed, who else but a deeply insecure person would feel the need to impress others with a gold Rolex, a $50,000 desk and an admin that looks as if she just stepped off the catwalk? Grandiosity encourages jerkitude because it reduces everyone else to an audience that by definition is less important than the "top dog."

My suggestion: The true opposite of grandiosity is gratitude. The more you focus on gratitude--especially towards the people who helped make you successful--the less likely you are to become all puffed up with yourself. Take special care to avoid claiming that you're a "self-made man" or "self-made woman." Even if you were born in poverty, you're standing on the shoulders of giants.

4. Wealth

Successful CEOs make money, which is as it should be. However, science has shown that as people acquire more wealth, they become less empathetic. For example, drivers of luxury cars are more likely to cut off other drivers at an intersection or force a pedestrian to jump out of the way in a crosswalk. CEOs are far from immune from this tendency. Indeed, CEOs who've been very financially successful (in my observation) are usually much bigger jerks than those who are only moderately so.

My suggestion: Beyond a certain level of comfort for you and your family, the only good reason to acquire more wealth is to help make the world a better place. Many of the world's billionaires have come to this conclusion and are busily figuring out how to give away their wealth where it will do the most good. That's a good model to emulate.

5. Role Models

And as we're talking about role models, I strongly suspect that some CEOs become jerks because their heroes (usually Steve Jobs) often acted like a jerk. What today's CEOs don't understand is 1) Jobs was a unicorn; standard rules don't apply, and 2) Prior to 1980, the screaming CEO was cultural shorthand for ineffective jerk.

My suggestion: Find better role models. Rather than idolizing the turn-of-the-20th-century CEOs who threw tantrums, read about the great leaders of history--in business, politics and warfare--most of whom are justly famous both for their humility and their ability to remain reserved and dispassionate.