The advantages of a ceramic knife are that it is lightweight, won’t rust, and is thin and sharp. A disadvantage is that it has poor elasticity and the edge can easily break off when cutting hard things. The user’s guide that comes with the knife should make these characteristics clear and easy to understand. Having the blade break when cutting a hard corn cob is not the responsibility of the manufacturer or seller, nor could the knife be considered a defective product. There are many types of knives, food materials, and uses. When purchasing a knife, explain to the seller what you want to use it for and choose a knife that suits your purposes.