Well water is harder on a water heater than treated town water, and out here that is usually the reason one fails early.
Iron and sediment build up faster
If your well has iron or hardness in it, sediment collects in the bottom of the tank far quicker than it would on treated supply. That is what causes the rumbling and popping, and it is why elements fail again a year after being replaced. Flushing helps; treating the water helps a great deal more.
Check the anode rod
On well water the sacrificial anode rod does more work and wears out sooner. Replacing one is inexpensive and can add years to a heater. On a rural property it is one of the more worthwhile things to have looked at.
Heaters in outbuildings
Where a heater sits in an unheated utility room or outbuilding, freeze protection matters as much as the unit itself. That is worth checking before winter rather than discovering in January.
What is worth repairing
A thermostat, element, thermocouple or gas valve on a tank under about eight years old is usually worth fixing. If the tank itself is leaking, it has rusted through and no repair will hold — we will tell you plainly.