If a player is to enchant an item in an enchantment table, and die afterwards, the options for enchanting are reset.

Say you were to enchant a tool. The enchantment options for other items and that tool have a decent chance of changing. If, for say, a sword were put into the slot and the 3 options were X, Y, and Z. Then the player dies. When they come back and look at the options for the sword, they will have reverted to those available before anything was enchanted by the player. You would expect to be able to die and have the enchantment options remain the same as before you died, but this is not the case.

This could, besides ruining a person's day, or be used as an exploit to receive an infinite amount of the same enchant, say eff4 silk1 unbr3 on every tool.