Alterable things can be updated, enhanced, or fixed, but do not change into something else. Pants that are four inches too long are alterable, and you can hem them to the proper length.
Though alter and change might seem the same, there is a subtle difference. When we alter something we change only part of it. For instance, we humans are alterable because we can cut our hair or paint our nails or pierce our ears. Our clothing is alterable because we can change the way it fits or dye it a different color. If you're turning pants into socks and princes into frogs, you're not altering them. You've discovered magic.
