OO is a good fit for programming a lot of important types of software, such as GUI's or 3D graphics, where it is convenient to model the program data as consist

OO is a good fit for programming a lot of important types of software, such as GUI's or 3D graphics, where it is convenient to model the program data as consisting of widely different types of data structure, having a common interface, and which are easy to add new types to without having to change existing code. Other than that, most use of OO is really just applying the language's OO structures to software idioms that exist outside OO, such as modules, or data hiding, or closures, and so forth. The only times OO actively sucks is when you're trying to do non-OO stuff in a highly-OO language, such as trying to do algorithmic code in Java.