What Is the Economic Rationale for a Miner to Always Prioritize Fee-Paying Transactions?

The economic rationale is based on rational self-interest and profit maximization. Miners invest significant capital in hardware and electricity, making them profit-seeking entities.

Since block space is a limited resource, a miner's best strategy is to fill their block template with transactions that yield the highest fee-per-byte. Including a zero-fee transaction represents an opportunity cost, as that space could have been used for a profitable transaction.

Prioritizing fee-paying transactions ensures the miner achieves the maximum possible immediate revenue from the block they successfully mine.

How Do Transaction Fees Change Based on Network Congestion and Block Space?
What Is the Economic Rationale for Increasing the Cost of Additional Votes?
What Is the Potential Impact of an “M-of-N” Scheme Where M=N?
How Does a High Volume of Zero-Fee Transactions Affect Network Congestion?
How Do Transaction Fees Influence the Ordering of Transactions in a Block?
What Is the Economic Consequence of Limited Block Space?
How Does a Miner Decide Which Transactions to Include in a Block?
What Is the Opportunity Cost of Including a Zero-Fee Transaction in a Full Block?

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