Visual Basic 1.0 was a major earthquake throughout programming. Before VB1, you had to use C, C++, or some other horrible development environment to create Windows applications. Programmers literally spent weeks just drawing windows on screens with picky, detailed, hard to debug code. (The same thing you can do by dragging a form from the toolbar in a few seconds.) VB1 was a hit and gazillions of programmers immediately started using it.
But to make the magic happen, Microsoft made some major architecture compromises. In particular, since VB1 created the forms and controls, they didn't allow the programmer access to the code that did it. You either let VB create everything, or you used C++.
VB 2 through 6 maintained this same architecture. Microsoft made some very clever updates which gave programmers a lot more control, but in the final analysis programmers still couldn't integrate their code with the VB code. It was a black box - and not in the good OOP way either. Another way of saying this was that the programmer didn't have access to the internal VB "objects" and another way of saying that was that VB6 still wasn't fully "object oriented".