From Oilprice.com:
Often the most important turning points in markets, and in this case the oil market, happen with a whimper rather than a bang. The ongoing crash in the oil market is mostly associated with OPEC’s fateful 2014 Thanksgiving Day decision to abstain from a production cut, thus sending the oil prices tumbling down by close to 10 percent in a single day. This was perhaps the price turning point, however this wasn’t the fundamental turning point, the latter goes back to August 2013.
First, let’s set the stage. For decades, the oil market operated under a simple formula: