A fish rots from the head. This is used to imply that when an organisation has problems, it is the fault of leadership. While that may have merit, the metaphor does not. Fish rot from the gut, where the wet, bacteria- and enzyme-laden guts rapidly liquify and then rot. I’m sure I don’t need to go any further, you get the picture, and you don;t want to start imagining the smell. I decided not to test the other fish saying “after three days fish and visitors start to smell”.
It’s always darkest before the dawn. This is used to impart hope and encourage perseverence – if things are really bad right now, then they can only get better. Not only is this sentiment not true (it is amazing the ability of situations to further deteriorate beyond what you thought was rock-bottom), but in fact it is darkest when the sun is on the directly opposite side of the earth from where you are standing. So if sunset is 7pm and sunrise is 7am, it will be darkest around midnight. Preferably in the country where there are no street lights, under a cloudy sky with no moon.
A watched pot never boils. Clearly if it has heat applied to it and has fluid inside it, it will boil. Your watching or ignoring a pot doesn’t actually stop it from boiling or otherwise. The Hawthorne effect does not work on inanimate objects. This saying refers to time being relative – when you are waiting for something (good) to happen it seems to take forever. On the other hand, bad things seem to come around quickly.
This is the end of the very short list of sayings that aren’t true. What other sayings annoy you?