Building things that nobody was waiting for without a sound businessplan. Grossly underestimating required technical knowledge and investment being a close second.
Based on some comments in this post and the posted article, it seems we are assisting to a power shift, I wonder who will replace the US and how long will it take.
That happens every time an empire declines. The Roman empire had a globalized economy, and that ended up collapsing into the medieval period of hyper-localization. The collapse of the Dutch and British empires had similar results. The American empire is collapsing now, and globalization is the first casualty.
Fun fact: Victorian England even had several very successful uber-like businesses (phone ordering aggregators in this case).