What Is the Main Factor Determining the Residual Value of a Two-Year-Old ASIC Miner?
The main factor is the miner's power efficiency (Joules per Terahash) relative to the newest models and the current cost of electricity in the secondary market's target region. If the two-year-old miner can still generate a profit in a very low-cost energy environment, it retains residual value.
The current cryptocurrency price and network difficulty also play a significant, volatile role.