Bitcoin security expert Andreas Antonopoulos recently said in a podcast that profitability will not lead to concentration of the mining industry. In the long run, the profitability of miners does not only depend on economies of scale. During the halving period, the least efficient mining union shut down the machine for fear of high electricity bills, resulting in reduced difficulty. As a result, early miners in unprofitable areas were able to get back on track and achieve profitability. Therefore, Antonopoulos asserts that profitability does not necessarily depend on the size of the mining company. The factors that lead to mining concentration are more related to the geographic availability of basic chips, geographic availability of cheap electricity, and comfortable regulatory areas.