And when you start getting to where it can take 10,000 miles to find a mistake, it takes a while to actually figure out which it is. Is software A better than software B? It actually takes a while to figure it out because neither one of them makes the mistakes -- would take a long time to make mistakes. So, it's actually the single biggest limiting factor is how long does it take us to figure out which version is better? Sort of a high-class problem. Obviously, having a drone fleet is very helpful for breaking this out.