There are certain phrases used by English speaking people all over the world on a regular basis, phrases which have gone beyond the realm of idiom or cliché and become an inherent part of the English language.
But no matter how common the phrase there are people who will misuse, mangle and mix up the words in that phrase, defending their version with confidence.
How many times have you heard someone say “one in the same” “hunger pains” or “I could care less” when they really mean “one and the same” “hunger pangs” and “I couldn't care less”?
It may seem like a small and insignificant difference, but if people are going to use these phrases so often they might as well be saying them correctly!
See 17 Common Phrases You've Been Saying Wrong Your Whole Life here