Sometimes it is appropriate to trade execution speed for programmer productivity. A financial model, for example, may be useful for only a short period of time, so it’s more important to create the model rapidly than to execute it rapidly. However, most applications require some degree of efficiency, so C++ always errs on the side of greater efficiency. Because C programmers tend to be very efficiency-conscious, this is also a way to ensure that they won’t be able to argue that the language is too fat and slow. A number of features in C++ are intended to allow you to tune for performance when the generated code isn’t efficient enough.

Not only do you have the same low-level control as in C (and the ability to directly write assembly language within a C++ program), but anecdotal evidence suggests that the program speed for an object-oriented C++ program tends to be within ±10% of a program written in C, and often much closer[22]. The design produced for an OOP program may actually be more efficient than the C counterpart.