Say, you have a huge system with tight memory constraints. Almost every programmer who's created an instance of any object now has that instance in contention for resources on this system. The free memory is going lesser and lesser and other resources are also facing the heat. The garbage collector is not very effective (as garbage collectors we know are). There is a very large pool of objects that do not have any reference and are left to their own. Now instead of instantiating your own objects, you can simply request one off the pool and work with it however you like (regardless of what type the object was) and change its type to the type you want it to (coz they're all after all instances of the same base class).

Now the question is, would you still instantiate your own object or just request from the pool? If it were a fact that once this system is down, you'll never be able to develop and deploy a single program ever again, would you still not care for it?

If only my mom was a programmer, I could have easily explained why I want to adopt a kid and not make my own. :/