Just too much growth, too fast, and raising costs which kicks lower income people to the curb:
‘Seattle journalist Knute Berger tells Business Insider that Amazon’s original headquarters has displaced minority communities there, driven up housing costs, and swelled the city’s population of homeless people. Seattle is also in the nation’s top 10 cities with the worst traffic, and doesn’t have a public transit system good enough to alleviate traffic pressure. I’m thinking of my city, Pittsburgh, as I read about Seattle’s troubles. Our housing costs are blessedly cheap to begin with, phew. But I can’t imagine any part of the city handling 50,000 employees worth of traffic. And our public transit kind of sucks.’
Original source: Why you city should avoid Amazon HQ2