Bear market is kind of an eye-opener for you and reality check for your investment decisions
And this is the whole thing. Bear market allows you not only to see where your investments are going
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Interestingly, we have little indication of a bear market. All economic and business metrics appear positive and hint at growth
As another famous dude - John Keynes - said, the market can stay irrational longer than you can stay solvent (or something to that tune). From this perspective, it doesn't really matter if the outlooks are bullish and metrics are positive. Anyway, personally I stick to a very simple definition of a bear market. It is the one which goes south for long enough time to consider it in a long-term downtrend
If prices continue to decline, the market is infested with bears, end of story