So how does weariness exactly work? Becease there seem to be two massive problems with it.
The first is that it seems to affect combat a lot. And it does so in a clearly unrealistic way. If you get to very weary you slowed down to a point that any enemy can easely get multiple attacks off on you becease you take so long to attack to the point that it is nearly crippeling to your melee capability. This is completely rediculous. The only things that would be able to slow a human down like that in a fight for their life would be running completely out of breath or phisical pain and injury (both already in game) but in no way could this be soley do to weariness. This is largely becease adrenaline and the fight or flight response will make sure that you will use your body to the full extent you can even if it means risking injuring yourself in doing so.
The second problem is the fact that the effect it weariness has on combat isn’t made clear to the player in any way. You can gather from it’s discription and the messages you get that you will take longer to do certain task (a quick check of the log will conferm so) but their is no reduction to your speed their is no obvious sign that weariness can be hugely detrimental to your melee capabilities untill you are engaged in melee and you notice that something is off.
A way to remedy this would be to remove the effect of weariness on attacking. This could than be replaced by more more visible and realistic effects in the form of penalties to your stats and speed at higher levels of weariness. Ranging form a minor speed reduction (~2%) at weary to significant (but not debilitating/crippeling) penalties to stats (STR,DEX) and speed (~10%) at higher levels. Additionally there is actually a real risk of overexertion injuries if you exert your body so much while weary so there should be small chance to damage yourself every time you attack, dodge and block if you get to the very weary stage (<1%) or the extremely weary stage (1%).