Sales errors may be inevitable, but they’re not unavoidable. Here are the 10 most common mistakes that sales reps make, along with an easy way to correct them.

1. Neglecting to develop sales skills.

• Why you do it: You’re too busy with the day-to-day pressures of making your numbers to spend the time necessary to learn new skills and hone old ones.
• The inevitable result: You will plateau at a certain level of selling, and never fulfill your potential as a sales professional.
• How to avoid it: Ask a respected peer to monitor your sales interactions and provide advice about where you need work. Then schedule a regular time every week to work on those skills.

2. Forgetting to prime your pipeline.

• Why you do it: When you’ve got plenty of prospects and customers, it seems like a waste of time to generate more opportunities.
• The inevitable result: When your current slate of clients runs out of steam, you’ll have to hustle to build your pipeline, and experience some lean weeks without commission while you do it.
• How to avoid it: Schedule quality time for cold-calling and asking for referrals and other lead-generation activities. Then execute those activities until you’re certain that you’ll have customers to work with, no matter what happens in the future.

3. Failing to qualify prospects.

• Why you do it: You’re so excited that the “customer” is willing to talk that you don’t want to burst your bubble by discovering that they’re not really a customer.
• The likely result: You’ll spend hours and maybe days developing an “opportunity” that will generate exactly zero revenue for your firm and zero commission for your wallet.
• How to avoid it: In the very early stages of the sales cycle, ask questions that will reveal if the prospect really needs what you’ve got to offer and (more importantly) has the money to buy.

4. Delaying follow-up on prospects.

• Why you do it: You’d rather enjoy the fantasy of winning the deal rather than the (much more gritty and possibly disappointing) reality of actually selling to them.
• The likely result: What was originally a hot prospect becomes a cold prospect, and, eventually, a dead prospect.
• How to avoid it: Schedule follow-up activities immediately after the customer contact. Check your calendar every day to ensure that follow-ups don’t fall through the cracks.

5. Proposing a generic solution.

• Why you do it: You don’t have the time to customize your presentation or solution, so you just propose what worked last time or (worse) something concocted by the marketing group.
• The likely result: The prospect will be less than enthusiastic (to say the least) when it becomes clear that the solution is just a cookie-cutter intended for anyone.
• How to avoid it: Don’t fool yourself into thinking that your generic solution will fill the bill for everyone. Instead, ask questions that uncover real customer needs, then build and present a solution that matches those needs.

6. Trying to negotiate too soon.

• Why you do it: You want to close the deal, so you enter in discussions of price, delivery, etc., before you’ve secured agreement that a financial transaction is going to take place.
• The likely result: Rather than negotiating terms, you’ll negotiate price, which means that you’ll get a lower price than you otherwise would have secured.
• How to avoid it: Before final negotiation, establish an overwhelming need for your product, and your product alone. Ace out the competition and leave no other option that can satisfy the customer’s requirements.

7. Delaying too long to close the deal.

• Why you do it: You’re afraid the answer will be “no” and want to avoid that horrible feeling of losing the deal.
• The likely result: If you miss the right point to close, the deal may never close. Other priorities and roadblocks will eventually emerge, making it harder (and perhaps impossible) to close the deal.
• How to avoid it: Throughout the sales cycle, position for the close by confirming that the discussions are on target. When there are no substantive issues left to address, make a final check for agreement and then ask for the business. Just do it.

8. Continuing to sell after closing.

• Why you do it: You’re expecting the customer to say “no” so you don’t hear the “yes” when it happens.
• The likely result: Best case, you’ll end up offering discounts and perks that will degrade the profitability of the deal. Worst case, you could accidentally surface objections that could completely scuttle the deal.
• How to avoid it: Listen to the customer. When you get a “yes,” stop talking, smile, and take the order. It’s that simple.

9. Forgetting the post-sale follow-up.

• Why you do it: You’ve moved on to other opportunities and can’t be bothered with last week’s news.
• The likely result: You’ll slowly destroy your reputation, because customers will think you’re only in the business to make a quick score.
• How to avoid it: Same as following up on prospects. After each sale closes, schedule a series of follow-up phone calls and email to check on the customer’s status.

10. Failing to build long-term relationships.

• Why you do it: Too many opportunities, and too little time.
• The likely result: The easiest customers are always repeat customers. You’ll constantly be building your pipeline from scratch, which means more work for less money.
• How to fix it: Think of selling as a way to help people, and to change the world for the better. Honor your customers and your relationships, just as you honor your friends and family.

Geoffrey James is the author of several books, hundreds of business articles, and currently writes the popular Sales Machine blog on CBS Interactive’s BNET website.