I've been in and around sales teams for decades, been writing about sales for about 15 years and have been personally coached by dozens of the world's top sales trainers. Even so, sometimes I make dumb mistakes. Here are a few of them.

1. Demonstrating every feature.

The first thing I sold as a professional was an automated publishing system that I had programmed myself. Like any engineer (which is what I was at the time), I was extremely proud of what I'd built.

As a result, whenever I gave a demo to a prospective customer, I would show every menu and every function. I assumed that the way I'd designed the software was exactly the way that a customer would want to learn about it.

I did demos this way for several years before I realized that customers were only interested in getting a job done and had no interest whatsoever in all the cool features that I'd stuck inside the product.

Lesson learned: Give demos that show how to solve a specific customer's specific problem.

2. Presenting too many facts.

My first marketing job involved promoting the concept of "document databases" as a solution to information overload. Whenever I present the concept to customers, I'd spin through a long list of facts that explained the size of the problem.

Not surprisingly, after a few minutes most customers were glassy-eyed. Fortunately, I ended up working for a guy who'd been a marketer at Proctor & Gamble. He suggested that, rather than facts about information overload, I instead start my presentation with a showing a desk with papers on it, I would then start talking about all the wonderful breakthroughs that came from computers, like word-processing, scanners, email, etc.

Each time I waxed lyrical about how much easier computers were making our lives, I click to the next slide, which showed even more papers on the same desk. By the time I'd gotten to the present, the desk was so piled with papers you could barely see the desk itself. That presentation always got a laugh and it definitely made its point.

Lesson learned: To make important points, don't use facts. Instead, use a story that everyone relates to.

3. Discounting after the close.

This only happened to me once, but this mistake is so incredibly stupid that I'm embarrassed to even write about it.

One time I was developing a sales opportunity that I really, really needed to close, so much so that I was ready to offer a pretty big discount just in order to land the customer. During the conversation, the customer closed the deal for me, saying something like: "OK, let's go forward with this."

I was so desperate to close that I didn't realize that I'd already won the business and instead surfaced the discount, which the customer quickly accepted.

When I told a friend about this, his comment was: "Geoff, there's a lake in upstate Maine named after you: 'Lake Schmuck.'"

The real problem, of course, was that I entered the situation in a state of desperation. I was thinking about myself rather than the customer. If I'd been paying attention, I would have heard the deal close and left well enough alone.

Lesson learned: Don't let your emotions get in the way of listening to your customer.

4. Caving on a last minute demand.

In a way, this mistake is even more embarrassing than the previous mistake, because I actually knew I was making this mistake as I was making it!

After trading emails with a potential client, we talked on the phone. We defined her needs and I proposed a solution. When the subject of payment came up, I played it perfectly. Rather than quoting a price, I asked: "What's your budget for this?"

The client gave me a number and I agreed to it. I repeated the arrangement out loud in order to make certain that I'd gotten it right. Deal closed. After we ended the call, I wrote a letter of agreement and sent it along with a standard contract. So far, so good.

Next day, I get a response email from the client with a new and unexpected demand. I have many times written about last minute demands. My advice: never give in to them, because 1) it results in more last minute demands and 2) it ruins your credibility.

Nevertheless, even though I knew it was a stupid move, I agreed to the demand. I hardly need tell you what happened next: another last minute demand, then another, and finally the deal fell through.

Lesson learned: Once you've come to an agreement, never agree to a last minute demand.

5. Selling before assessing needs.

Probably the most common selling error in the world is to think that what you're selling is so wonderful that you can just assume that the customer wants it. This generally happens when you've been successful for a while.

I've fallen prey to this kind of thinking repeatedly in my career and it's probably cost me many thousands of dollars in lost business. And rightly so. After all, if I can't take the time to find out how I can truly help a client, why should I expect a client to hire me?

The real problem here is that I sometimes let my ego get in the way of my purpose. My purpose is to help other people become more successful. My ego is only useless baggage that comes along for the ride.

Lesson learned: Selling is always about the customer; it's never about you.


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