Fees are a function of transaction size and network volumes (how congested the network is). Transactions are processed in blocks, storing up to 1MB of data. Hence, a sudden spike in activity often leads to network congestion – transactions waiting to get verified. In such situations, miners target transactions with higher fees first. In other words, the more a user offers in fees, the faster their transaction is likely to be verified.
Bitcoin Miners’ Revenue From Fees Rises Suggesting the Onset of Major Bull Run
