Routines enable athletes to evaluate competition conditions. For example, bouncing a ball in a volleyball service routine supplies the server with information about the ball, the floor, and the state of her muscles. This information can then be used to properly prepare for her serve. Routines also enable athletes to adjust and fine-tune their preparations based on those evaluations or in pursuit of a particular competitive goal. This adaptation can involve adjustment to the conditions, rivals, competitive situation, or internal influences that can affect performance. Just like adjusting a race-car engine to the conditions of the track, air temperature, and weather, routines adjust all competitive components to achieve proper performance.