Some baseball team defenses will be fairly standard and universally accepted in how they are deployed. Yes, there could be slight variations or deviations to each defense based on abilities or lack of abilities of defensive players. For example, if one player is more fleet a foot than another, or one has better arm strength or one player lacks lateral movement, then having a contingent plan in the deployment is always acceptable.
However, when deploying a particular defense, such as an aggressive bunt defence or a particular first and third play, an array of variables must be considered before entertaining the defensive scheme for your team. Situations always vary from game to game and indeed, from inning to inning, hitter to hitter and frankly pitch to pitch or count to count. Consider this then, there are numerous ways a defensive situation can change, but largely it will be based on the following influencing factors.