Fans enjoy seeing these athletes play so much that they are willing to pay to watch a game or match. Professional athletes are performers or entertainers, a lot like actors and musicians. They must perform well in each game or risk losing each game. If they don't play well, they won't last long in this job. They must be in the best possible shape.
Most modern athletes work out all year, both during the season and in the off-season.
They must be able to perform their jobs at the highest level at all times. For these and other reasons, this kind of job can be quite stressful. During the regular season, professional athletes often practice 2 or 3 hours a day. They may have other duties related to the team as well, like going to meetings or watching films about the opposition. Athletes often move to the place where their team is located.