The cost of mining is relatively high. First of all, you have to have a large number of mining machines, which have a high configuration and a large amount of electricity, and the temperature of the mine is also processed. And now it's getting harder and harder to dig, so I don't recommend digging! 
One of my friends told me that if the price of bitcoin falls a little more he will stop mining because he told me that the mining is very costly and they make just few hundred dollars in a month because of the bitcoin price in the market. If the price rises they will receive good profit but if the price falls, it will not recover even the mining expenses. Therefore they will have to quit.