Engineering Homework Help

While the ideal vapor-compression cycle maintains saturated vapor at the compressor inlet, it is common to adjust the mass flow rate and the evaporator conditions to maintain a level of superheat at the compressor inlet. Why do you think this is? What side-effects might this have on the cycle? 

Also, What is the reason it is common to adjust the mass flow rate and the evaporator conditions to maintain a level of superheat at the compressor inlet? Just a few sentences in the chat.