ALL great products &amp; services eventually face intense, margin eroding competition .  $AMZN, $GOOG, $NFLX, $AAPL, $TSLA.  2020 seems to have forgotten that truism.  Great (fiction)book abt Edison, Westinghouse &amp; Tesla (himself) is a good reminder &amp; fun read. https://t.co/NQY9GGvO3Y