Why must the spray valve of the rotary compressor in an MVR system be installed at the compressor inlet rather than the outlet?

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As the title suggests, I consulted several compressor manufacturers but didn’t get a clear answer. My understanding is that the main purpose of spraying water is to eliminate overheating; normally this refers to overheating of steam. However, rotary compressors are positive-displacement pumps, and during the compression process caused by the compression of steam, the rotors can overheat and risk getting stuck due to expansion. Since the superheat degree of the incoming steam is limited, a small amount of sprayed water is used to eliminate overheating, but more importantly, it serves to create wet steam that enters the compressor chamber and vaporizes there, thereby preventing the rotors from overheating. Hence, unlike centrifugal compressors, the spray valve is installed at the inlet. I wonder if my understanding is correct?