Mining. In cryptocurrency networks, mining is a validation of transactions. For this effort, successful miners obtain new cryptocurrency as a reward. The reward decreases transaction fees by creating a complementary incentive to contribute to the processing power of the network.
It matters because the actual coffee flavor is extracted from grind better at higher temperatures. I'm not a scientist but I trust those that have done the research and they say that the optimal temperature for hot water in a coffee pot is between 195-200 degrees or just a little under boiling.
1 Fresh roasted, quality whole bean coffee. Don't grind yet!  Coffee is best brewed at temperatures between 92 and 97C, or about 192F and 204F. Guess what - a kettle, just off the boil, once poured, is at the top end of this temperature. Air cools the first bit real quick.