I enjoy the great privilege of working with Dan McKinley, whose blog is at mcfunley.com. He doesn’t post very often and his posts are reliably great. I want to call out one post specifically … Testing to Cull the Living Flower. Here’s one sentence:

When growth is an externality, controlled experiments are the only way to distinguish a good release from a bad one.

In it, he argues for why sites that are enjoying rapid growth must use A/B testing to build features if they want to be confident that they are making a measurable, positive impact on that growth rate.