Corporations are an outdated means of organizing industry. While they can innovate upon existing technology, invention and discovery are avoided, as the length and uncertainties in such undertaking can eat into shareholder returns. While there are exceptions, this selective pressure is seldom overcome. This competitive evolutionary model forces participant companies into a race to the bottom. Corners are cut, labor stiffed, and customers squeezed in order to draw greater and greater profits -- or else run the risk of loosing out to more ruthless competition.
In the same way large firms were able to stabilize disruptions in the supply chain through vertical and horizontal integration (thus outliving smaller, regionally managed businesses), mixed economies stabilize the shocks and disruptions of large firms, with the added benefit of re-focusing the output of industry to common goals, rather than to enrichment of a narrow few.
Overall, it is essential to see corporations as a phase in the conscious and unconscious evolution of human endeavor - a tool in the industrialized toolbox and not an end goal unto itself. It's also important to learn to write for yourself, or you'll be clowned on quite easily.