Often when you consider a candidate for a new job or an employee for a promotion you consider the interaction you had with him or her. If it has been limited and in a specific context (such as one interview), you make up your mind about what you saw. For instance, this is a highly confident but respectful person.

But that is only one perspective, and often people who worked with the individual have a different view. That is what we convey at Checkster with simple charts that put in perspective the rating of all people who interacted with the candidate/employee, either as a colleague or as an interviewer. Often surprises arise and decisions may change.

The best analogy I found recently on this is the perception we have living on earth that our planet is mostly water, until you see another perspective:

This picture shows the size of a sphere that would contain all of Earth's water in comparison to the size of the Earth. The blue sphere sitting on the United States, reaching from about Salt Lake City, Utah to Topeka, Kansas, has a diameter of about 860 miles (about 1,385 kilometers) , with a volume of about 332,500,000 cubic miles (1,386,000,000 cubic kilometers). The sphere includes all the water in the oceans, seas, ice caps, lakes and rivers as well as groundwater, atmospheric water, and even the water in you, your dog, and your tomato plant.

Source: http://ga.water.usgs.gov/edu/2010/gallery/global-water-volume.html