I think builder has more to do than just creating an object. When creating object it should ensure that created object can handle all future operations. While creating object it should make sure all invariant are met for future operations.

Example.. When creating an object cat, object builder will ensure if the cat can drink milk. If it can not drink milk, then it will not create the object, and instead respond with message "cat can not drink milk".

This concept is bit different from the way we instantiate object and handle exceptions with in the object. Advantage of object builder is, there will be valid objects in the system all the time.