'unhelpfulness' originates from the English prefix 'un-' meaning 'not' and the word 'helpful', which comes from the Old English 'helpful', where 'help' meant 'to assist'.

'unhelpful' changed from the Old English word 'helpful' and eventually became the modern English word 'unhelpful' by adding the prefix 'un-'.

Initially, it meant 'not providing assistance', and this meaning has largely remained the same in modern usage.