An arrow hit on a lightly armored or unarmored person might knock them off their feet. Trying to continue doing anything with an arrow sticking out of you is difficult at best, although whether your problem is just agonising pain or your body going into shock (‘freezing up’) at the injury depends on where and to what depth the arrow is lodged.
Attempting to pull out an arrow will only make things worse - historically, arrowheads were not firmly adhered to their shafts. Sometimes they were attached with a blob of candlewax, but usually the archers would simply spit on the shaft before sticking the head on - thus, snapping the shaft (a lot more difficult than Hollywood makes it look, as they were made from the hardest woods available so they would fly further and straighter), was completely pointless, as pulling on the shaft would leave the arrowhead inside the wound.
The only way to remove one was to widen the wound, either with a knife or by wiggling it around. And as archers would usually stick a number of arrows in the dirt at their feet in preparation for firing them, arrow wounds had a strong tendency to become badly infected. The only way to deal with an arrow quickly was to push it through until the head came out the other side. A hit from an arrow was never Only a Flesh Wound.
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