Because Bitcoin has the longest life span. It has existed for 9 years and many believe in its safety. In addition, big investors like Bitcoin because it gives them more profit than other coin

In each country, the difference in Bitcoin exchange rates is different. Because the supply and demand gap of each country is different. A few days ago in the UK I saw the price of Bitcoin is only half the price.

Bitcoins are often used as an investment vehicle or as an intermediary for trading other Altcoin. Bitcoin has not become a currency as it is unstable in its price difference too much