Bitcoin miners will stop getting block rewards once the total supply in circulation has been reached.When all of bitcoin has been mined, transaction fees will be the only source of income for miners. The absence of new supply will cause bitcoin's price and purchasing power to change. Because Bitcoin is so rare, consumers and investors will find it more appealing.
Also, because arithmetic bit-shift operators within the Bitcoin network adjust mining rewards' decimals to the nearest integer. The total count of Bitcoin that can ever be mined will probably be less than 21 million because this can occur every time a block reward is decreased in half.