R-Zero’s Daily Elder Scrolls Headcanon
Numerous spikes and protruding minor blades covering Daedric weapons are oftentimes not a result of a conscious design choice of their creators, but rather a side effect of their origin. Made from fossilized blood of a Padomaic and purified by Daedric substances, they “…retain echoes of preternaturally prolonged suffering endured during manufacture…” which results in spontaneously sprouting such appendages during both the cooling off period and after drawing blood from the enemy.
Daedric weapons grow more and more spiky over time, with the oldest of them becoming nigh unusable. Some say that eventually such weapons transform into some kind of Dremora-like minor daedra, but such metamorphosis has never been recorded and is surely just another hearsay.