Characterization

Depending on the type of show, there are different methods directors can use to lure the audience into connecting with the characters of the show:
In shows where the same characters are seen in every episode, like The Real World, we get to know what these people do every day and how they act; we actually get to know who the characters really are. This leads us to feeling very happy when the couple you wanted to end up together finally hooks up or when the annoying roommate that is just there to make everyone's life miserable is finally kicked out of the house.
In shows where there are different characters every episode, the director is challenged to create a connection between the audience and the characters in a short amount of time. In Wheel of Fortune and other game shows, sometimes we feel inclined for one specific person to one over another. Maybe it's because that player is a single mom and so are you or maybe it's because the the young man needs the money in order to pay for his wedding and you also know someone who is engaged. Those small qualities in a person can attract you to root for that character versus the other.