‘The question of what amounts to “such care as in all the circumstances of the case is reasonable” depends on assessing not only the likelihood that someone may be injured and the seriousness of the injury which may occur, but also the social value of the activity which gives rise to the risk and the cost of preventative measures.” (Lord Hoffmann)

To what extent should these factors be balanced against each other in determining whether a defendant has breached the standard of care? Critically discuss this statement in light of the authorities.