Scarcity written into the code
The Bitcoin protocol sets a cap of 21 million units and no central authority can raise it. New issuance is cut in half roughly every four years: the latest halving took place in April 2024 and the next is expected around 2028 (CoinGecko, 2024). That predictable monetary policy, known in advance by every participant, is the foundation of its store-of-value thesis.