The only way today's characters die in an MMO for good is if we personally delete them. We wouldn't want our hard earned time and loot to go to waste now, would we? Of course not. There have even been a slew of rants and raves about who owns virtual property and even players committing suicide because they get so attached to the things they've earned. What if we turn the focus from item-centricity to something else? The whole idea is probably best expressed in an example.
Let's say I create a character named John. I choose John to be a hardy warrior, best suited to the ways of a blade and shield, with heavy armor. This suits John and he makes a good living as a warrior, starting out with his home town's militia and slowly working his way up to be a war hero while serving in the local magistrate's army under the Queen. He's led a great life, battled many foes and collected many spoils. He ages, like most men do and soon finds himself doing more desk work than adventuring. His skills begin to slip and he realizes that soon, he will have to father an heir to continue his legacy or all he's done will be forgotten in time. Of course, John doesn't want this, so I create his son George. George has inherited many of his father's traits and John instills some of his wisdom in the ways of the sword before he is fully retired and spends the rest of his days in the castle, mulling about and advising the Queen's battlemasters. Meanwhile, George like the idea of swords, but he's not sold on the idea. He definitely knows how to use one, but he's more interested in the budding idea of magic and its uses for the good of the kingdom. He goes off to the academy and incorporates what he's learned with the idea of magic and in the end, evolves the warrior class into a battle mage class.