The more credible mediums are the ones best schooled in reading people and presenting common situations and events in terms vague enough that someone who wants to believe can easily shoehorn their experiences into these vague suggestions. They then read the mark (that would be you in this case) for cues as to how to proceed further along with whatever suggestion they make that appears to have landed. You see the same thing in astrology: ascribe common strengths and weaknesses to each sign and it’s easy to see yourself and others in them, if you want to believe.