Instead of waiting for confirmation of reversal, “buying on weakness” means to go ahead and buy a long position (or cover a short position) while a stock is in the middle of a downtrend, in the hopes that it will reverse soon and the preemptive move will allow you to capture the entire upside.

Upswings can happen very quickly, and failure to prepare for them can cost investors a lot of money. Buying on weakness is intended to put the investor in a position for maximum gains, as well as preventing losses on a short position. This is one part of the “buy on weakness / sell on strength” mantra, which is essentially the same thing as “buy low / sell high”.

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