In the year or so since I've been writing for Inc.com, I've received several hundred emails from readers asking for assistance and advice. From this experience, I've observed that the following 10 basic selling errors are surprisingly common.

1. Answering Objections the Customer Hasn't Surfaced

Though it's a good idea to anticipate objections that the customer might have and prepare reasonable answers to them, it's a horrible idea to surface those objections yourself--because you've just created an issue that probably didn't exist. Explaining away something preemptively can also make you seem defensive and unsure of the real value of your offering.

Fix: Never start any sentence with "You may be wondering..." or "Perhaps you're asking yourself..."

2. Leaving the 'Next Step' to the Customer

I've read dozens of so-called sales letters and sales emails that end with a suggestion that the customer should call or contact the seller "if you're interested" or "in order to learn more." The people who send these letters always complain that they don't get any responses.

No kidding--you're asking the customer to do your work for you.

Fix: Keep the ball in your court. Try substituting a closer like this: "I will call you next week to discuss whether it makes sense to discuss this matter further."

3. Selling Features Rather Than Results

Incredibly, some people (usually marketing folks) believe that customers buy a product because it has desirable features. They therefore rattle off a list of those features, hoping that at least one will pique the customer's interest.

In fact, customers care only about the results of purchasing a product and the ways it will affect their lives and their businesses.

Fix: Figure out why a customer buys your product rather than somebody else's. Then sell that result, using the features to buttress your ability to deliver that result.

4. Faking Intimacy

Like it or not, the minute you're positioned in somebody's mind as "a person who is trying to sell me something," you're fighting an uphill battle to win trust. Under those circumstances, the absolute worst thing you can do is to try to "suck up" by acting smarmy.

The most common manifestation: brightly asking, "How are you doing today?" at the beginning of a cold call. It makes people want to puke.

Fix: Remain personable and professional--but no more--until such time as you actually forge a friendship, which typically takes weeks.

5. Writing a Sales Proposal Too Soon

Although proposals can occasionally help develop an opportunity, in most cases, the proposal requesting (and writing) process happens after the prospect has already defined the problem and (probably) defined the solution as well. Because writing a proposal takes time and effort, it's usually a bad investment unless you've got the inside track on the sale.

Fix: Write a sales proposal only after you've got a verbal agreement.

6. Talking More Than Listening

I've written about this problem repeatedly in this blog, but the error is so common that it bears repeating. When you're selling, it's all too easy to get excited and nervous and then try to "drive the sale" forward by talking or giving a sales pitch. Customers find this extraordinarily irritating.

Fix: In your mind, redefine selling as a passive activity that consists mostly of listening, considering, and reacting to what the customer does and says.

7. Wasting Time on Dead-End 'Opportunities'

What with voice mail, gatekeepers, and a challenging economy (not to mention the craziness of global competition), it sometimes seems like a miracle when you actually get into a sales conversation with a live human being.  When that happens, the possibility of making a sale can become so seductive that you don't want to spoil the dream by asking questions that might reveal this as a false opportunity.

Fix: Within the first five minutes of your first conversation, ask questions that will reveal whether the customer has a real need--as well as the money to satisfy it.

8. Failing to Follow Through

The sad truth is that, to customers, people who sell are guilty until proven innocent. Building a customer relationship is about gradually building up enough trust to overcome the natural antipathy that most people feel toward sellers.

Because of this, you're not going to get any slack if you fail to deliver when promised. Drop the ball, even once, and you're probably out of the game.

Fix: Get religious about your to-do list and scheduling specific events. Make only commitments that you're 100% certain you can keep.

9. Treating a "Close" as the End of the Process

Maybe it's the result of unfortunate terminology, but a lot of companies and individuals take "closing the deal" to mean that the sales activity has ended. Nothing could be further from the truth.

The real work happens after you've closed the deal--because that's when you can start building the kind of relationship that will eventually generate follow-on business and referral sales, both of which are far easier and profitable than winning new business.

Fix: Always aim for long-term relationships rather than short-term revenue. That way a "close" is the beginning, not the end, of the process.

10. Asking for a Referral Too Soon

Some sales training programs recommend asking, "Do you know somebody else who might need my product?" even when prospects say they're not interested. Other programs suggest asking a similar question when you've closed your first sale to a customer.

Both approaches are naive, because customers in their right mind do not put their own reputations at risk by recommending somebody whose ability to perform is unknown to them.

Fix: Ask for referrals only after the customer is delighted with the products or services that you've sold.

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