Hi folks!
I reading book Agile Software Development Principles, Patterns, and Practices by Robert C Martin and i must say the thinking process is so far great, the example case with payroll system shows how difficult OOP really is.
Why OOP difficult?
In my opinion its difficult if requirements are not static , but rather dynamic and with proper dev process approach is only then possible to catch all client requirements.
I can only recommend reading this book, because it gives the right approach towards OOP.
Best Regards
Alexander