Microsoft is more like a corporate organism. Institutions have a rigid, self-perpetuating organization. Microsoft is more like a natural organism in that it has a constantly shifting organization designed to perpetuate the company, not the individual departments of the organization. In an institution, a single department can bring down the entire unit because they're looking out for their own good, not the entire institution's. In Microsoft, individual departments are expendable if they are not working in the best interest of the entire organism.
Institutions become ingrown and outdated because they loathe change.
Organisms are constantly eating from the outside and digesting the results, making the outside world a part of them. This keeps them outward looking and constantly changing, based on what they've taken in from the outside world. But like other organisms, Microsoft's goal is continued life, through whatever means are necessary. Kill or be killed if necessary. It can never rest or depend merely on what worked in the past.