To prevent dust and little curious fingers from getting into the electronics. Easy enclose the cabinet. However, the electronics can also get warm, so a cooling system is needed. I decided on a passive ventilation system has intake vents at the front above the kick board, and outtake vents at the top of the back panel. Air goes in and out in a linear fashion. At least in theory... but I think it's a good theory. The mesh is 5mm woven stainless steel.