Slightly more seriously: the problem with cliché "labelling" is the same as that of stereotyping. The reason why stereotyping is possible is because the stereotype exists and it's exactly the same for trading clichés.
Basic trading/financial knowledge (like all of the simpler kinds of knowledge) is axiomatic in the sense that an idea or truism can be encapsulated in a neat and easily comprehensible phrase or proverb, more often than not in a rhyme. You can instantly see that "The trend is your friend until the bend at the end" belongs in the same category as " A stitch in time saves nine" though they are separated by some 300 years. The meanings of both are obvious and endless repetition makes them trite .......but that doesn't detract from their veracity.
Vive le cliché!