It's not. It's trading lingo. If the pricing was on a downturn "losses", then an upward move is a correction.
Except that in practice nobody says that. I've worked with both large financial institutions and tiny hedge funds going back nearly 30 years, traders are cognitive bias on legs. There's a reason Wall Street has a statue of a giant bull but not of a bear.
> The practice of referring to increases in the price of an instrument as "gains" but any decline as a "correction" is bizarre.