One time and i will never understand why... i was at school with my mates on lunch hour and we walked down the street to the local town as it had a really good chip shop which was far better and just as expensive as the school lunches. Anyway after getting our lunch and heading back to school i had a pocket full of change and it was pissing me off hearing it jangle every step i was taking so i started looking at it to see if there was anything worth keeping or not.

It was mostly coppers (1 and 2 pence pieces) so i tossed those as we walked and then i had a slew of 5 pence pieces too and i tossed them. But for some reason my friends who never cared about the coppers being tossed, took umbrage at my tossing those little shiny 5 pence pieces.

And i sort of said "oh i have always hated the 5p coin, its useless" and i went on a diatribe for no real reason to sort of justify why i was throwing away about a half dozen coins.

Anyway it sort of stuck and for the next 5 years every time i got change from lunch or whatever i ended up having to toss the 5 pence coins or my mates would start asking questions.

The annoying thing is that... by the time i finished highschool i had done it that frequently that i sort of accidentally trained myself to actually hate 5p coins and even 16 years later i still toss them and it spread to 10 and 20p coins too. Albeit this is now extremely rare since almost all my purchases are online now or using contactless payment.