Big market players will pick the right time before entering the market to carry out their transactions. For example, if I want to buy a large amount of CAD, I will do this during the North American session and will usually spend the Asian and early European session trying to ensure that the price doesn’t move too much. Similarly in AUD or even in JPY, the most liquid time is often during the Asian session and for the GBP and the CHF, mid-morning in Europe is the best time. If I wish to buy a large amount of CHF for instance, I would ‘lean’ on the currency during fairly illiquid Asian hours and then start buying once liquidity improves into European trading.