Edward Niedermeyer's book _Ludicrous_ spends some time on this subject. According to Musk's own statements, Tesla invited less than 200 customers to a trial, an

Edward Niedermeyer's book _Ludicrous_ spends some time on this subject. According to Musk's own statements, Tesla invited less than 200 customers to a trial, and then declared that there was insufficient demand. Niedermeyer points out that conducting even a single customer battery swap allowed Tesla to book about $100M in extra ZEV credits over the years; according to his own anecdotal observations, there was considerably more demand than Tesla claimed, but Tesla did not seem to be overly motivated to make the program work.