I heard somewhere that if we wish someone younger than us then say "best of luck" and if we wish someone older than us then say "all the best". I don't know how much of this is true. Will you please describe the difference between the phrases and also which to use under the different contexts?
Learn English – “All The Best” vs “Best of Luck”
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Best Answer
As a native American English speaker, I don't know if there is much of a difference. At the very least, no one has ever taken me to task for using either one with the inappropriate age group.
In fact, they both seem to be ellipses of the phrase I wish you all the best of luck, it just depends on where you cut the phrase.