The 21 million bitcoin limit was set by its creator, Satoshi Nakamoto, in the Bitcoin protocol.

1. Controlled scarcity: The idea of ​​a limited supply is central to Bitcoin's value proposition as "digital gold." By limiting the total amount of bitcoins, it seeks to create scarcity, which can help preserve their value over the long term.

2. Inflation and deflation: A fixed supply counteracts the inflation that can occur with fiat currencies, which can be issued without limit. By having a cap, the supply of Bitcoin is expected to become more valuable as demand increases.

3. Reward model: The number of bitcoins is generated through a process called mining, where miners are rewarded for validating transactions. The reward for mining blocks is halved roughly every four years (an event known as "halving"), contributing to gradual scarcity.

4. Similarities to Gold: Satoshi Nakamoto was likely inspired by gold, which also has a limited supply. It is estimated that there are around 21 million tons of mineable gold on Earth, which could have influenced the decision to set a similar limit for Bitcoin.

5. Ease of Use: A number like 21 million is manageable and easy to work with from a technical and psychological perspective. It allows for divisions into smaller units (such as satoshis, where 1 bitcoin = 100 million satoshis) and makes it easier to adopt.

In short, while the number 21 million is not directly correlated to economic growth, it is designed to encourage scarcity and offer an alternative to the traditional monetary system, which may influence its value $BTC