The safest way to try and get what you want is to try and deserve what you want. It’s such a simple idea. It’s the golden rule so to speak. You want to deliver to the world what you would buy if you were on the other end.
The Liskov Substitution Principle is a fundamental concept in object-oriented programming, stating that objects of a superclass should be replaceable with objects of a subclass without affecting the correctness of the program.