[robocat]

Classical inheritance enforces that a method can only be overridden by another method in a subclass.

Prototypical "inheritance" allows different types of values to be assigned to the same symbol.

E.g. if you have a method bob() on a prototype, you can set object.bob = 'astring'; and it isn't an error.

[colbyAFTrustedK]

That has more to do with a language opting out of having fixed types than it does with class-based versus prototype-based inheritance.