If you've been around the market long enough, you'll notice a trend: the short term bottoms tend to coincide with the financial pages and websites bringing on talking heads that tend to have a bearish perspective, and mentions of bear markets or market crashes being imminent tend to have a greater frequency.
To back up this observation, I decided to check out Google Trends. Notice how the following terms tend to coincide with short term bottoms in the market:
Search Term: BEAR MARKET
Search Term: STOCK MARKET CRASH
Peaks in these search terms came at the height of the market panic in August 2015, and before that, during the significant market drop of 2011 when the US lost its AAA credit rating, then before that, a very choppy and persistent fear-driven market during the 2008 financial crisis.
Today's search densities are at similarly elevated levels. Contrarians take note.