[solnic]

I stopped using statefull objects that make decisions based on their state, in general, validations aside. I don't "delete objects", I make changes in the database instead. When it's a complex operation that requires making decisions based on some information, I simply construct that piece of information from the data in the database and have an object that will know how to use that information to decide what to do. It's a different philosophy that is against some typical OO concepts but I found it to be simpler.

If there's an integration with an external system that can provide data that are valid format-wise but violate some rules defined by my system I still do not need to construct objects that may have broken state. I just build an object that will provide information from that external system which is valid according to rules defined by that system and then ask another object if this piece of information is valid from my system point of view. There's no need to encapsulate everything in one place, in fact, it would be almost always too much responsibility anyway.