Guards

[Hrthuma ibn Marwan]

Originally Posted by Rich

On Nihonto (Japanese swords), the tsuba (hand guard) is not meant to
prevent the opponents swords from striking the hand, but rather to
prevent the users hands from slipping onto the blade. Hence many are
small and somewhat "delicate" sukashi (cut out) styles. It is rare to find
a tsuba with a sword cut on it.

Rich S

The Japanese Sword Index
http://www.geocities.com/alchemyst/nihonto.htm

^That is one good reason.

You also have to see the "ideology" behind the guards on the swords. Some might be for protection, some might be like the tsuba.
Then also, the European swords were meant for sheer power, but other swords might have been built in order to be swift and quick etc..

What I like is the european sabres and pirate swords. Usually have a good protection plus, good maneuverability