"Market corrections" occur every 20 months, but less than a third of these actually becomes a bear market. Recessions almost always lead to bear markets, and bear markets outside of recessions are uncommon. For that reason, discerning whether a recession is imminent can help determine when an innocuous correction is probably the start of a sinister bear market. Volatile equity prices alone are not sufficient.
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Why bother following the economy? Why not just follow the price of equities?
It's true that equities fall before the start of most recessions. Take the last 50 years as an example. There have been 7 recessions and the S&P has peaked and started to fall ahead of all except one (the S&P peaked with the start of the recession in 1990). On average, the S&P has provided a 7 month "heads up" that a recession is on the way. That's enough for even the slowest investor to get out of the way. Enlarge any chart by clicking on it.