'carefully-watched' originates from the combination of 'carefully' and 'watched', where 'carefully' is derived from 'care' meaning 'attention' and 'fully' meaning 'completely', and 'watched' is the past participle of 'watch', meaning 'to observe'.

'carefully' evolved from the Old English word 'carful', and 'watched' from the Old English 'wæccan', eventually forming the modern English term 'carefully-watched'.

Initially, 'carefully' meant 'full of care or concern', and 'watched' meant 'to keep vigil'. Over time, it evolved to mean 'closely observed with attention to detail'.