One of the keys to successful sales performance is to understand the needs of the person you are selling to. Equally important is understanding how to communicate with them, and understanding how behaviors work is a key component in this.
Some people like to be given facts while others want a fast-paced interaction. Some people want to make decisions quickly while others want to take time. Selling at the wrong pace can have disastrous results, and behavioral assessments can help enormously here.