Sometimes the best way to sell is to emphasize what the prospect would lose by not buying from you, not just what they would gain. This principle seeks to exploit the natural human tendency to avoid loss. Most people are risk averse. They take buying decisions in a default safety mode.
In addition, some prospects have this mortal fear that the salesperson is a sweet-talking person quick to over promise and under deliver. To mitigate this, highlight the potential losses.
For instance, if you are selling an excel training package, rather than stress how acquiring an advanced excel certification will enhance a prospect’s chances of getting a better job, threaten them with the likelihood of a job loss when the current application or package is phased out.