My explanation was that it is the most important goal.
Jim Collins gave a similar explanation.
It is an audacious goal to achieve in a 10 to 30 year time frame.
Jim Collins his Harvard Business Review talks of envisioned future as a part of the vision.
The words 'envisioned future' were used by Koontz and O'Donnel in their explation of grand strategy.
According to Jim Collins, a well-conceived vision consists of two major components—CORE IDEOLOGY and an ENVISIONED FUTURE. A good vision builds on the interplay between these two complementary Yin-and-Yang forces; it defines “what we stand for and why we exist” that does not change (the core ideology) and sets forth “what we aspire to become, to achieve, to create” that will require significant change and progress to attain (the envisioned future).
Core ideology is the combination of the objectives of the company and values of the company. Goals are derived from the objectives. Goals are the target for achievement in future. Goals are the vision. But goals can be many and are related to many dimensions. Vision is one of the goals that encompasses many goals within it and rallies the entire personnel of the organization.
Visit the website of Jim Collins