High Liquidity in Forex
The foreign exchange market is the most liquid market globally, which means there are a large number of buyers and sellers seeking to trade at any given time. Every day, individuals, companies, and banks conduct more than 5 trillion dollars in currency exchanges, and the vast majority of these activities are for profit.
The high liquidity of forex means that trades can be completed quickly and conveniently, so transaction costs (or spreads) are typically very low. This creates opportunities for traders to speculate on price movements of just a few pips.
Global Average Daily Trading Volume $BTC
 $SOL
Source:
Forex: Bank for International Settlements' triennial central bank survey (2016)
Stocks: Calculated based on data from the World Bank (2017)