It's not about the doubling, it's about how the distribution changes as you gather more data and get closer to the actual mean (e.g. if you had EVERY possible customer ever, like cable companies).
Take Tesla, for example. Its first customers were enthusiasts, but the mean of that group is not the mean of all current Tesla customers - they would look very different, and had Tesla optimized for the latter we'd be looking at a very different outcome.
Take Tesla, for example. Its first customers were enthusiasts, but the mean of that group is not the mean of all current Tesla customers - they would look very different, and had Tesla optimized for the latter we'd be looking at a very different outcome.