If you made an enchanted book in survival mode with the max amount of enchants possible, the book becomes unusable. This is caused by the cost being calculated based on what the book has in total, instead of what's applicable to the item being enchanted. For example, my pickaxe with no enchants should be given Silk Touch I and Efficiency V, yet when using a maxed enchanted book on it in the anvil it says the cost is too high. When using an enchanted book with only Silk Touch I and Efficiency V, it works.