To do that, he administered personality tests to one thousand B2B salespeople who worked at some of the world's leading companies. Here's what his research showed along with a few of my own thoughts.

• 91 percent of top sellers had medium to high scores for modesty and humility.
  What? Winning salespeople aren't totally egotistical? No. They don't have to be the center of attention. They don't need to flaunt their wins. Instead, they want their customers to take the credit for making wise decisions. And they truly value the support they get from their own colleagues along the way.

• 85 percent of top sellers were highly conscientious.
  Highly conscientious. Not just average. Essentially, that means they don't leave anything to chance. They research, study and think about how they can help their customers make a good business decision. They keep things moving, involving the right people at the right time. They're reliable hard workers.

• 82 percent of top sellers showed extremely high curiosity levels.
  Extremely curious. That's fascinating. Top sellers want to learn more — about their customers, market, products, value propositions, triggering events, the buying process and the individuals they deal with. With a deep hunger for knowledge and information, they ask more and better questions.

• Top sellers were 30 percent less gregarious than average sellers.
  Contrary to popular opinion, being super friendly is not the key to sales success. Extroversion does not trump introversion. Sellers who are overly focused on building deep personal relationships have a harder time challenging their customer's thinking and getting them to move off the status quo. They don't want to rock the proverbial boat.

• 84 percent of top sellers scored very high in achievement orientation.
  Not just high — very high. That means they have a goal in mind and that they're damned sure going to do everything in their power to achieve it. Top sellers keep track of progress and are brutally honest with how things are going. They seek out potential obstacles so they can eliminate/minimize them before they occur. They strategize, coming up with Plans A, B and even C. They never hope for success, they create it.

This is NOT the image that most people have of salespeople. Yet it is certainly my own experience working with thousands of sellers throughout the years.

Now, back to the actuaries. Believe it or not, these very smart people could identify with all the statistics above. They were modest, conscientious, curious, introverted achievers. Knowing this was the crucial first step. They had to see that it was possible for people like them to succeed.

That's how we all are. Yet all too often we make assumptions that limit our success. Perhaps more data would help!

Related: 3 overlooked productivity tips for sales reps