Salespeople are humans, and humans make mistakes. Unfortunately, when salespeople make mistakes, there are often accounts to be lost, money to be left behind, and clients to be disappointed. According to Dr. Kerry Johnson, a financial services expert and author of six related books, the errors made by the people in sales are often easy to fix, but just as easy to overlook. Following are five such mistakes, as noted by Johnson, and five ways to make sure they never cause another lost account again.

1. They fail to continue their education. This doesn’t mean that salespeople lack a master’s degree or fail to gain the proper amount of schooling. Instead, this refers to the lack continued learning you can gain from attending seminars, staying up-to-date with relevant articles, and by reading industry publications. To Johnson, this means, “They don’t constantly reinvigorate themselves.” And due to the ever-changing nature of sales, this results in the same old tactics with ever-dwindling outcomes.

2. They never become specialists. There’s nothing wrong with being more specific about your intended audience. As Johnson puts it, “Think about it. People get paid more to be medical specialists than they do to be medical generalists.” Though we’re often tricked into the “big-box” mentality that is encouraged by successful one-stop-shop retailers, this approach can often lead to a limited scope due to increased competition.

3. They keep bad company. All too often, salespeople give too much credit to what their friends, other salespeople, think. This can lead to negative thoughts and negative selling. Johnson says it best: “80 percent of your peers are only delivering 20 percent of the results.” By buying into the badmouthing and the complaining, you’re only hurting your ability to make up that missing 80 percent. Just remember: they’re out to get your business too.

4. They don’t listen. Asking good questions is important, but listening to the answers is essential. Salespeople often “jump the gun” by anticipating answers or reading between imaginary lines. For this one, go back to the basics. Try repeating an answer once you’ve heard it. Teachers use this method to make sure they’ve understood a student before responding to them.

5. They abuse or under-use technology. These salespeople hurt themselves by being on either end of a delicate spectrum. They’re either the people attached to their inbox or terrified of it. Technology is a tool to be used alongside human interaction–never in place of it. To the apprehensive salespeople who have yet to set up a Twitter page, consider taking a night class at your local community center to catch up or talking with your technologically savvy peers.

Learning to sell efficiently is an ongoing process. And while making mistakes is part of the game, being wary of unnecessary errors can save the savvy salesperson time, money, and a great big headache.