When calling for a medic, the medic immediately moves to the location where the player gave the heal command, regardless of whether or not the player is actually there. After the medic reaches the position where the command was given, he then starts to search for the player, and eventually heals the player. This is an inefficient way for medics to behave because they have to do more movement and "thinking" instead of making a beeline to the player. It also leads to many medics getting killed. Imagine this scenario: When the player, being injured, calls for a medic after being shot, he/she moves to cover while the medic runs into the open where you were just shot and gets himself killed, instead of moving directly to the cover you are behind.