'unpredictably-continued' originates from the combination of 'unpredictable' and 'continue', where 'un-' meant 'not', 'predict' meant 'to foresee', and 'continue' meant 'to persist'.

'unpredictably-continued' evolved from the combination of the words 'unpredictable' and 'continue', which were used separately in Middle English and eventually combined in modern English.

Initially, it meant 'to persist in an unforeseen manner', and this meaning has largely remained the same in modern usage.