Some warriors fight by strength and skill, others fight with wit and dexterity, and yet others wade into combat armed with knowledge and unwavering spirit. The Samurai is the epitomy of the latter path, they're warrior-monks who have understood that merely training ones body and spirit is not enough; and that likewise, memorizing complicated combat manuevers is a road whose gains are uncertain and transparent. Samurai instead choose to fully comprehend the origin and story behind any sword they find, and by doing so, they learn to invoke their very essence and mold that essence itself into supernatural effects. Because of the wonders they invoke upon the battlefield, many Samurai are often mistaken for being armored mages.
Bushido is an ancient art which focuses precisely on drawing on the latent essences of Katana, summoning their spirit to perform a supernatural task for the Samurai - each particular blade of renown houses a different spirit, and thus possesses a different ability, the only way to fully realize this ability is to learn the swords name and discover its story and its associated myths and legends, the powers the spirit invokes draw upon these legends one way or another and thus Samurai are wanderers, whenever they receive a new katana, they seek to understand its origin and learn its mysteries and by that empower themselves. Therefore, Samurai very rarely wield a single blade in combat, but instead carry several different ones, one or two of which they've understood - and in battle they change armaments often to wield different blades with different spirits, picking those most suited to dealing with the situation.
But as is expected, most swords do not have a story grand enough for them to possess hidden powers; and Samurai shun these blades, indeed - their loathing for blades without history and special origin is so great so as to have them refuse to consider them proper blades. Believing such a denotion worthy only of those blades they themselves carry; for this reason common merchants very rarely find customers in Samurai, for even the most exquisite blade is of less use to them than the dullest most fragile katana, whose story is both long and respected, such a blade would be turned into an unstoppable tool of battle in the hands of a skilled Samurai; as their very spirit and knowledge awakens its latent powers and turns it into a weapon of great supernatural qualities, fit to best even the newest and most impeccable of ordinary swords with ease.
A Samurai's goal is a simple one, they're loremasters of the blade - putting alot of research into finding a specific sword by tracing its story and its origins to its present location. Thus, by understanding a story, they learn to embrace the blades true power once they acquire it for themselves. Due to their research, most Samurai specifically search for a single blade at a time, and they know precisely which one they want - a Samurai never wanders aimlessly, for they know that every step they take brings them ever closer to their trophy. Its not unusual for Samurai to meet one another and find that they're searching for the very same blade, such happenings are invariably settled with a duel - as they believe that the one most worthy of the blade should have it. Whether they kill or spare their opposition varies from Samurai to Samurai, but they invariably claim a single blade in the losing Samurai's collection as a trophy. However, no Samurai is permitted to, under any circumstance take the blade handed out by the other Samurai's respective Dojo - as that blade is proof of their stature as a Samurai, and given to them personally through a serie of trials. But above all, its because these blades represent a future creed of Samurai, and by taking one, the Samurai would pledge themselves to take the responsibility of the other Samurai and found another Dojo of their own, this is a trouble that few Samurai are willing to do, and thus these blades are mostly left untouched.