that might be due to traders who come from various parts of the world and various countries that come in one place to exchange and trade so that the place of exchange never sleeps.
Trust me I really appreciate your words because I am not in favor to let the market sleep. It is open for people 24/7. People can invest any time no one can stop your income to get high if you will invest your money in to crypto currency, I am sure bitcoin will never sell my coin as it has plenty of profit for me, keep on investing so you will never find the market be down.