When I first became a sales person, no one ever told me about comfort zones. My boss said “do this” or you will fail. I didn't want to fail so I did it. Now as a sales manager who has trained thousands of sales people, I realize the biggest obstacle to most sales people's success and for more success to those who have some measure of success already is their "comfort zone".Over 5,000 books have been written on what to do to make a sale. There is enough information available for anyone to know what to do to make a sale. So, why do some people fail at a sales career? Or, perhaps worse, get in a rut of results that let them keep their jobs but to never excel? There are thousands of sales people in the "get by" category. They do enough to “get by” and keep their jobs, but nothing more.My contention is that their inability to leave their “comfort zone” is what's holding them back. When I started selling books door to door, I was told the first week don't worry about selling anything. Just see 180 people (30 a day), however it doesn't count if you don't tell them the price of the books and ask them if they want to buy. At the end of the first week I'd done it.That Saturday night, I went to the laundry mat to wash my clothes and as I put my clothes in the dryer I realized I had bought defective socks. My six new pair of socks were all wearing through the toes. Then it hit me. Each time I ask people to buy, I was so uncomfortable that I dug my toes into my shoes so hard it wore my socks out.I didn't realize it then but I had “comfort zone” issues. I had "closing reluctance". Some sales people have “closing reluctance”. Some salespeople have “call reluctance” and some have “follow-up reluctance”. Plus, there are many more comfort zone issues that we in sales face every day. So, why do some of us overcome comfort zone issues and others don't?First, most successful sales people realize what their “comfort zone” issues are. Psychologists tell us the solution to any problem begins with the recognition of that problem. You can never solve a problem you can’t admit you have. However, once you identify what's holding you back, you can do something. When I interview successful sales people and sales people who have had breakthroughs in their careers, they all tell a similar story. They say to get a “trick of thought” that helps you push through. Mine is a mantra I repeat over and over again. When I face myself and know I must do something uncomfortable to achieve what I've set out to accomplish, I repeat "I hate the price. I love the prize. I hate the price. I love the prize". This seems to get me over the hump.Another super sales person told me he just kept saying and writing at every opportunity "Glen Cunningham, Glen Cunningham". If you don't know, Glen Cunningham was the greatest miler of all time. He held the indoor world record and outdoor record in the mile consecutively. He won 21 consecutive international mile races. It had never been done before or sense. What is the point concerning comfort zones?When he was 8, he was in a school house fire and all of his skin was burned off both his legs below his knees. The doctor wanted to amputate but his mother wouldn't let him. He was bed ridden for 2 years. He began to walk and then he began to run. If you're a runner you will appreciate this. He had no toes on his left foot and only two on his right. HE HAD COMFORT ZONE ISSUES!So, when you think about your own comfort zone issues, it makes it easier thinking about those who had bigger ones. Find your own “trick of thought” but start by recognizing the comfort zone issues that are holding you back. If you do, your sales will increase. Remember, a rut is just a grave with the ends knocked out!