Open DevTools right now. Go to the Network tab, find the throttling dropdown, and set it to Slow 3G. Now reload something you built. Watch the blank white screen sit there for a few seconds. Watch the layout jump around as fonts and images land out of order. Somewhere in the world, someone is looking at that exact screen on that exact connection, right now, and they don't have a throttling dropdown to turn back off. "Optimize later" is one of the most common plans in web development, and i...