Strategy development is not a one-size fits all process. As Einstein stated "I think and think for months and years, ninety-nine times, the conclusion is false. The hundredth time I am right".
Strategy development is challenging and requires strategic thinking and ability to dig deep into the companies vision and mission, awareness of the dynamics of the organization, openness to new ideas, encouragement of creativity and innovation, the ability to see strategic alternatives and scenarios and link these to the budget.
The strategy must not only align to the vision and mission of the company, but also be clearly articulated and have associated performance measurements. These go beyond operational KPIs and focus on outcomes and results. Metrics and reported frequency are derived to drive decision making, measures team and organizations performance going beyond the individual.
In order to drive the strategy into the future, continuous process improvement is critical. Ensuring the organization understands work processes, how well the processes work, documentation, best practices, benchmarking, and continually improving upon the processes.
Sustainability of the strategic plan is how well the organization is focussed on the vision, plans, and initiatives, is there communication activities in place, are there motivational and support efforts to drive "doing the right things". Keep in mind that strategy is everyone's responsibility.