There was no big announcement. There was no single invention that spurred it. And you can't pin it down to a single technology. But there has been a great shift in the last five years. This shift in our expectations as consumers has happened gradually and almost imperceptibly.
This shift has been talked about as an 'on-demand economy' or the 'access economy.' According to Mike Jaconi (Co-founder of Button) who has written a considerable amount about this shift, "the on-demand economy will usher in a paradigm shift similar to what was seen with the advent of the internet in the late 1990s."
Simply put, this shift was created by companies that leveraged technology to create radically fast and frictionless experiences. The core tenets of this movement are speed and efficiency-make something hard, effortless, and immediate. Think Uber, Grub Hub, Amazon, or Carvana.
"If you study what the really big things on the internet are, you realize they are masters at making things fast and not making people think."