Learn English – origin of the expression “trying to catch a falling knife”

I'm not sure how common it is. (Sorry to profess ignorance, but I don't recall hearing it before).

When I Googled the phrase, I noticed almost all the links revolved around investing or finances. (Ah! No wonder a poor man like me hasn't heard it before...)

I thought this website explained it very well:

A falling knife security can rebound, or it can lose all of its value. As the phrase suggests, buying into a market with a lot of downward momentum can be quite dangerous. If timed perfectly, a buy at the bottom of a long downtrend can be rewarding - both financially and emotionally - but the risks run extremely high.

This site listed several investing cliches, including the falling knife expression, where it said:

"Never try and catch a falling knife. Wait for it to hit the ground then pick it up. The same applies to falling stocks."

A falling knife can land handle-side down (in which case it bounces), or blade-side down (in which case it sticks into the ground). If you're trying to catch the knife, and you catch the wrong end, you get hurt. Seems to be an apt metaphor.

The cliche is apparently well-used in investing circles. There's even a book with that title .

That said, I have no idea if its origins can be traced. It might just be one of those things that got uttered in the pit, and stuck.