Rivian started deliveries of its R1T pickup truck and R1S SUV not long ago and even won accolades for its cars’ qualities, but not all is golden in the EV startup’s empire. The company had its first earnings call two weeks ago and CEO RJ Scaringe let us all know Rivian will not be able to meet deliveries expectations. Now, Rivian’s CEO elaborates on the matter in a letter sent to customers.