reasons for missing abstract keyword [duplicate]

Question

What is the reason for not using abstract keyword in C++? As I read the only way to declare a class as abstract is to declare pure virtual function in it, which is a bit convoluted. Why isn't there a more direct way of declaring an abstract class?

Answer 1

I think that the main reason is unwillingness to introduce a new keyword. All was tried to do in the frames of C keywords.