Summer temperatures aside, Phoenix is a surprisingly good place for a city. It lies at the confluence of three major rivers (Salt, Gila, and Agua Fria) and the heart of Arizona's largest expanse of arable land. Secondly, most of the canals and infrastructure to convert that into usable land had already been constructed by the Hohokam hundreds of years before, when they had built what was then the largest canal network on earth. It was those canals that allowed the Phoenix area to be one of the most populous regions in precolumbian North America. No surprises then, when that infrastructure base would allow Phoenix to again support a massive population.

Why people came to Phoenix is a more complicated matter. Mexican immigrants came because the Arizona border was crossable decades earlier than the sister the ports in California and New Mexico. Chinese immigrants came to work on the railroads. Blacks came while moving west to California. And easterners came to exploit the minerals and resources overflowing from the territory.

I could go on for a bit, but I'm getting off track. I couldn't make the entirety of my post about current motivations because of the 20-year rule. However, the currently accepted logic for people moving to Phoenix is because it has jobs, cheap living costs, and Air Conditioning is available.