Filters are easy to forget because they do their work quietly. You do not see them cleaning the air, fuel, or oil while you drive. You only notice them when the car starts smelling musty, losing power, using more fuel, or acting like it has not been serviced in too long.
Pennsylvania state inspections and emissions testing can feel stressful when you are not sure what the shop is looking for. Your car might drive fine around town, start every morning, and still have a problem that keeps it from passing. That is what catches many drivers off guard.
A cold A/C vent feels simple when everything is working. You press a button, set the temperature, and expect cool air to show up. Behind that, the system is moving heat out of the cabin instead of creating cold air from nothing.