Bitcoin transactions are verified by miners, who are incentivized to do so. Mining is the process of verifying each transaction in the blockchain. Every time a miner verifies a transaction, they are rewarded with new Bitcoin.

These miners are rewarded for their efforts because the Bitcoin network relies on them to ensure the security and accuracy of the network. Without miners, the network would not be able to function without fear of double spending or other malicious activities.

The miners are rewarded for their work in Bitcoin, which adds to the circulating supply of Bitcoin. This creates an incentive for miners to continue to verify transactions and maintain the security of the network.

The reward for miners is currently set at 12.5 Bitcoin per block, though this amount is halved every four years. This is done to ensure that the supply of Bitcoin is kept in check and that miners continue to have an incentive to participate in the network.