Sound Source   

microphone selection  

placement 

room acoustics

The sound source chosen determines the microphone selection, microphone placement, and where in the studio the sound source should be.

 
In general the microphone picks up two things
The ambiance of the studio as the sound bounces off walls, furniture, etc., (reflected sound)  The source itself
(direct sound) 

The closer the microphone is to the source, the less reflected sound is recorded. 

The usual practice is to place the microphone as close to the source as possible. If you are recording voice, a closely placed microphone will pick up the performer's chest resonance - an important audio cue which indicates to the listener that the speaker is nearby. If you wish to give the perception of a more distant voice then adjust the microphone placement accordingly.