What Is the Primary Operational Cost for a Mining Pool Operator besides Infrastructure Maintenance?

The primary operational cost, aside from server maintenance and software development, is the payout cost associated with managing the reward system, especially under a guaranteed system like PPS. For the operator's own mining efforts, the largest cost is electricity.

However, for a pool operator who mainly facilitates others' mining, the biggest non-infrastructure cost is often the risk capital required for reward systems or security overhead.