I am on the quest to be a good OO-developer. OO intrigues me, because I understand the patterns, know why composition gives you more flexibility then inheritance, and more of such wisdom. However, I came to the conclusion that I know how to implement a factory of a singleton, but that I do not know how to come up with a robust OO design.
I have a bunch of books
They might be very good books, but they don't teach you to architect an application. I am often paralysed by some very basic decisions (example). I am looking for a book that teaches the when and why. There are many books about hammers and nails, but I have yet to find a book that tells you something about their practical relationship.
What book was most instrumental in making you a confident OO-architect/designer?
The best book I ever read about OO is Bertrand Meyer Object Oriented Software Construction.
Its huge but it was very useful for me. It covers every single aspect of OO design IMVHO.