Tesla was founded in 2003, Rivian in 2009. So Tesla took five years to start Roadster production, while Rivian has taken 12 years until first customer deliveries. Maybe Rivian will ramp faster. Sam Korus tracks the numbers and so far Tesla is ramping faster than Ford, making it the fastest ramping car manufacturer in American history. I wouldn't be surprised if some Chinese companies could go faster. It is much faster than what Toyota did. They are very methodical, which is why they have almost zero pure EV sales.