Every machine requires regular maintenance and upgrades over time. If you do not spend money on maintenance and upgrades of of machine, you have to pay more for a major repair facing in the future. The same logic applies to your air conditioner. If your AC or heat pump lack of maintenance, you can not enjoy a comfortable life.
Air conditioner is a unique machine, which is designed with care and technology. In most cases, it can serve you for a long time, without interruption or complaints. But, like other devices, it needs servicing and tune up from time to time.