How Do Different Nodes’ Mempool Sizes and Policies Affect Transaction Visibility?

Different nodes' mempool sizes and policies directly affect a transaction's visibility across the network. Nodes with a smaller memory limit or stricter minimum relay fee policy will reject or drop low-fee transactions more quickly.

This means a low-fee transaction may only be visible to a small subset of nodes, primarily those with more permissive policies. Reduced visibility lowers the probability that the transaction will reach a miner who is able and willing to include it in a block.

A more widely visible transaction has a higher chance of confirmation.