Why not use instanceof operator in OOP design?

Question

It has been repeatedly said that the instanceof operator should not be used except in the equals() method, otherwise it\'s a bad OOP design.

Some wrote that this is a

Answer 1

instanceof simply breaks the Open/Close principle. and/or Liskov substitution principle

If we are not enough abstract because of instanceof usage, each time a new subclass makes an entrance, the main code gathering the logic of the application might be updated. This is clearly not what we want, since it could potentially break the existing code and reduce its reusability.

Therefore, a good usage of polymorphism should be preferred over the basic use of conditional.