Let me share the harsh truth: the majority of HVAC failures occur because someone missed a step. Didn't calculate the load correctly. Used undersized equipment. Miscalculated the insulation needs. We've fixed dozens of these failures. And each time, we file away another lesson. Like in 2017, when we began adding WiFi controls to every install. Why? Because Sarah, our senior tech, got sick of watching homeowners waste money on inefficient temperature control. Now clients save 20-30% yearly.