University of Tennessee

Too Much of a Good Thing Is Actually a Bad Thing

July 26, 2021

Study Finds Surprising Link Between Over-Confidence and Sales Performance

In sales, where persuasion is a crucial part of the job, it makes sense that a lack of confidence would be detrimental to performance. However, a recent study from the University of Tennessee, Knoxville’s Haslam College of Business indicates that when salespeople are overly confident, their job performance may suffer even more. 

Emotional intelligence (EI) — the ability to identity, use, understand and regulate emotions — has long been recognized as a key factor in employee performance. However, the study shows that for salespeople to reap the benefits of EI, they also must have the right amount of emotional self-efficacy (ESE) — confidence in their ability to engage those emotions when interacting with customers. 

Alex Zablah (marketing department head, Gerber/Taylor Professor and Kinney Family Faculty Research Fellow at Haslam), Jonathan Hasford (assistant professor of marketing at Haslam), Blair Kidwell (University of North Texas), Broderick Turner (Virginia Tech) and David M. Hardesty (University of Kentucky) investigated how EI and ESE work together to enhance or diminish a salesperson’s performance. The team found that the interplay of EI and ESE — a combination called emotional calibration — is a better indicator of sales performance than either EI or ESE alone.

Emotional Calibration Builds Customer Rapport

Having high confidence, emotionally calibrated salespeople expect to do well when interacting with customers, so they can relax and focus on building customer rapport. A calm salesperson makes customers feel they are being heard and that their needs will be met. Because calibrated salespeople are good at discerning customer emotions, when they see that the customer is at ease, they become even more relaxed, which further enhances their performance.

Hasford was surprised to discover how damaging overconfidence can be in sales settings. The researchers conducted four multi-source studies across a range of industries to see how much effect emotional calibration has on sales performance. Their findings confirmed that salespeople who are emotionally calibrated (high EI, high ESE) achieve, on average, sales performance outcomes 351 percent higher than those who are emotionally overconfident (low EI, high ESE), 61 percent higher than those who are negatively calibrated (low EI, low ESE), and 37 percent higher than those who are emotionally underconfident (high EI, low ESE).

“Confidence provides a ton of benefits in interpersonal settings, and salespeople are often a confident group of people relative to the general population,” Hasford said. “Yet, salespeople who are overconfident in their emotional skills are by far the worst performers.”

Stress and Job Tenure Also Affect Sales Performance 

The sales benefits associated with emotional calibration may vary based on numerous factors. Gains resulting from improved customer rapport are most pronounced among salespeople who have been in their jobs for a relatively long period and have more experience interacting with customers. Regardless of job tenure, emotional calibration appears to produce less benefit when salespeople are experiencing even low amounts of stress.

These insights indicate the importance of a supportive work environment, the researchers said, and can guide recruiting, retention and training efforts. Managers may need to screen their sales staff and provide feedback to minimize the negative effects of overconfidence. 

Whether looking to close a sale or hire new employees, salespeople and management would be wise to consider the customer’s perspective, according to Hasford.

“Displays of eagerness and aggressiveness to close a sale are often ineffective,” he said. “Instead, customers seek calmness in salespeople, which is more effectively displayed when a salesperson has high EI and high confidence in their skills.”

The study, “Emotional Calibration and Salesperson Performance,” was published in the Journal of Marketing in February 2021 and is available online


Stacy Estep, writer/publicist,