Bitcoin's mining difficulty adjustment, occurring every 2,016 blocks (roughly two weeks), significantly impacts miner behavior and network security. When difficulty rises due to increased hash rate, miners with less efficient equipment may face higher operational costs, potentially exiting the network if unprofitable. Conversely, a drop in difficulty, often after a hash rate decline, incentivizes miners to rejoin as rewards become easier to earn. This self-regulating mechanism ensures the network maintains a consistent block time of about 10 minutes, preserving stability. For network security, higher difficulty strengthens resistance to attacks like 51% attacks, as more computational power is needed to dominate. However, sharp difficulty spikes could centralize mining among larger players, risking decentralization. Overall, the adjustment balances miner participation and secures the blockchain effectively.