It's a trade-off, because it's convenient to not have to check that objects are non-nil when you send messages to them. With experience, you learn to deal with

It's a trade-off, because it's convenient to not have to check that objects are non-nil when you send messages to them. With experience, you learn to deal with code that requires non-nil objects via assertions: NSAssert(array, @"Array can't be nil.");