America's most successful entrepreneurs are people who have the ability to see how to solve the problems we are faced with. If you've bought or had someone repair a humidifier, furnace or water heater you helped inspire someone who was thinking of a way to keep you comfortable. Engineers put a lot of thought into making things we will buy to make our houses more comfortable. In every home the air is moving, changing the condition of what's inside.
All those things we buy to help us feel better( like our furnace ) and we need to listen to our furnace if it starts to rattle.