How Does the Concept of ‘Hash Rate’ Relate to Mining Profitability?

Hash rate is the number of calculations a miner can perform per second to find a valid block hash. Profitability is directly proportional to a miner's hash rate relative to the total network hash rate.

A higher individual hash rate increases the probability of solving the next block and earning the block reward. However, as the total network hash rate increases, the individual share of the rewards decreases, unless the miner also increases their hash rate.