According to Peter Lynch, sooner or later this statement will prove to be true. However, this may be much later than one would expect and in the meantime it may fall much lower...
He also writes something about fishing and having reached the bottom...
" trying to catch the bottom of a falling stock is like trying to catch a falling knife. It is usually a better strategy to wait until the knife reaches the bottom, gets stuck, swings back and forth for a while and finally comes to rest before trying to catch it.
Trying to pick up a rapidly falling stock leads to painful surprises because you usually catch it at the wrong moment.
If you are interested in buying a turnaround stock, you should have a more sensible reason than that the stock has fallen so far or that it looks like it can only go up from here."

Quotes from:
One Step Ahead of the Stock Market - Peter Lynch - 1989
(S. 334-336)