Is it really necessary to ask such a question? Consider what would happen if the heat were not dissipated, and you'll quickly come to the answer.+

Clutch uses friction to transmits the torque, hence it gets heated up .when heated up the plate material behavior will change from what it is designed for. Like co-efficient of friction may change affecting the torque output. It also can distorted the plated due to uneven distribution of heat in plate and also in the surrounding area. Hence affect the performance of clutch and in some cases catastrophic failure.

So the clutch functions properly and damage is prevented.