You don't need anything extra for Bitcoin. The computers and devices that existed even before Bitcoin was sufficient enough to secure the network. Profits ince

You don't need anything extra for Bitcoin. The computers and devices that existed even before Bitcoin was sufficient enough to secure the network. Profits incentivized miners to invest in specialized devices. If Bitcoin's price stood still, hash power would eventually find equilibrium, and no new resources would be invested. But if price keeps going up, of course people chase more coin.