A problem is if you use RAII for other resources than memory, for example files. You want to put the close function in the destructor then, but close can throw an exception. http://www.cplusplus.com/reference/fstream/ofstream/close/ (Of course the solution is easy, you wrap close in a try catch block, but as alwaya all the solutions are easy in c++ but this is one of the surprising corners, which might be done more often wrong then not)