The hardest thing
Strategy is about direction and destination. It is the way to the vision. It is intended to marshal the organization's resources and energies to pull it to a new, better place.
Let's postulate a law of strategic difficulty, which has three parts:
(1) The greater the differential between the current course of the organization and the envisioned future for the organization,
(2) the more entrenched the organization is in its current vision and direction, and,
(3) the fewer resources the organization has that will help it move to the new vision...
...the more profound the strategies need to be and the more difficult the strategies will be to implement to get the organization to the vision.
More simply, strategic difficulty is determined by the amount of difference between the new vision and the old, the degree to which the organization continues to "own" the old vision and the strategies it had been pursuing to reach it, and the resources it can commit to reach the new vision.
The evidence that the law of strategic difficulty applies in the real world abounds. Start-up organizations find executing strategies difficult not because of entrenchment or differential (unless the entrepreneurs are truly into something they know nothing about), but surely because of resource deficiencies. On the other hand, for example, the "old" AT&T found it difficult to change from a regulated monopoly utility to an agile, marketing-based organization because of both entrenchment and also little experience in marketing (a resource deficiency). Conversely, for IBM to morph from mainframes to PCs to computer services, while certainly not easy, was helped because of the lesser differential the organization had navigating in somewhat familiar computing waters, and the deep computing-related resources of the organization.
How can you use the law of strategic difficulty when finding a vision and the strategies to reach it?
Obviously, your organization will find it easier to move to a new vision that builds on rather than is in an entirely different direction than the old vision. You will find it easier to move to the new vision if the case for the new vision and moving off the old one is made most apparent and urgent to your organization. You will find it easier to move to the new vision if resources are at hand or can be mustered to execute the necessary strategies.
All this can be a tall order for some organizations and in some circumstances. The hardest thing to achieve is for an entrenched organization that does not have deep pockets to do something entirely new. In fundamental ways, it remains committed to the "old," with limited resources to commit to the new.
Wherever your organization is, recognizing the degree of difficulty as you plan the journey is important so that preparations can be made to reduce the risk of the difficulties you will encounter on the trip. Think of the Wizard of Oz. Despite rust, flying monkeys and a cranky wizard, remaining reality based and trusting in the vision, Dorothy got back to Kansas.