Why doesn't Amazon choose a city that almost meets their criteria and invest the wealth they generate there back into the city? Then we get more good cities instead of overinvesting into any single city.
Most of their criteria aren't that flexible. Nobody is going to reroute interstates or move airports for Amazon. They might be able to get a transit line extended or a new station added to an existing line. Population/education might be negotiable if there is a site with awesome transportation. Cell coverage would certainly be fixable, though, if the local officials commit to reasonable planning approvals, and can co…
Well, there's the Kindle Whispernet thing. I'm in Australia and was impressed when the first Kindles came out and "they just have 3G, no configuration/questions asked - and Wikipedia is free." The high-level involvement and agreements required for worldwide "just works" connectivity (which is not technically amazing, but politically impressive) means that fixing local cellular would likely be a shoo-in and require no drawn-out anything. Chances are the HQ building(s) will have cell towers factored in at the blueprint level.