So, it is an underground heat pump system. The weakest link is the compressor. We had to replace our heat pump/compressor every 5-10 years making it a very expensive heating system.
My heat pump has lasted at least 15 years.
Overall, heat pumps save money for most people, providing about 3.3 times as much heat as you'd get from direct heating by electricity. Typical open-loop systems like the one described in the article will give you back 4 to 5 times the heat.
Maybe you just had some bad luck.
To the compressor:
You are The Weakest Link! Good-bye.