The Click Potential metric within the Keyword Analyzer is the predicted chance of getting a click through to your website if your result occupied the top position of the SERP. A keyword's Click Potential score can be impacted by the presence of SERP Features that would hinder searchers from clicking on an organic website results. Different SERP Features on the page will have a different effect on that keyword's Click Potential.
For example, a keyword with a News block on the results page will have a higher Click Potential than a keyword with an Instant Answer because with the News block, you have more than one potential opportunity for a click. With an Instant Answer, Google provides you with information directly on the SERP and the rest of the results will suffer a less-than-average click through rate.