Design Goals for MFC
The AFX group had five main priorities for their new framework:
• Deliver a real-world application developed using C++ and object-oriented
techniques. 
      Simplifying the Windows API 
      SimUsing the Knowledge You Already Have 
      A Firm Foundation 
      Keeping It Small and Fast

• Deliver an application framework that simplifies Windows development for
both new and experienced programmers.
• Allow developers to leverage their existing knowledge of Windows.
• Establish a foundation for Windows developers to build large-scale applications
that utilize the latest Windows enhancements, such as Object Linking and
Embedding (OLE) and Open Database Connectivity (ODBC).
• Keep the framework small and fast.


Source:
MFC Internals