I've been meaning to explore some thoughts about injuries, wounds, and character death in adventure games for some time. In doing so, I've inevitably had to tackle the subject of Hit Points.
In the past, I've considered that obviously hit points correspond to actual wounds. The key arguments here being the effect of armour, and the existence of poisoned weapons. This argument often goes hand-in-hand with the idea that a combat round is six to ten seconds, and that a single attack roll reflects a single swing of a sword.
The contrary view is that obviously hit points reflect endurance, stamina, and will to live. The arguments here being that no mere mortal could expect to endure multiple wounds, and that an 'attack' merely represents the cumulative effect of swordplay over a round lasting a minute or so. This was the interpretation favoured by Gary Gygax et al, seeking to replicate the duel between Robin Hood and the Sheriff of Nottingham in the 1938 Errol Flynn movie.
Where I've landed is a compromise. Why, yes, this fence is mighty comfortable. No human could expect to endure - as even a moderately high level character can - multiple blows from a swordsperson who really means it. Much less a fire ball spell. So hit points must, on some level, represent all those good intangible things. But, at the same time, the presence of various effects contingent on scoring blows does necessitate actual wounds.
So, my conclusion is this: hit points represent the gradual wearing down of defences and the accumulation of minor wounds. Inconsequential cuts, scrapes and bruises. And I think this suits the genre well. Heroes in media - whether film, or TV, or literature - aren't slowed by flesh wounds. It takes a meaningful hit to do that. One which only comes when their defences are worn down, or by some combination of luck and skill from a foe.