Product vision (or Product Master Plan) is link between company strategy and roadmap. Activities may vary depending on the situation but may contain market opportunity analysis, technology, value promise analysis and capability analyses.
During value proposition analysis, own strengths and weaknesses are identified and benchmarked against competition. Product vision may also contain more comprehensive channel, partner and financial analyses. Value Proposition Canvas from Strategizer is one possible tool to be used as a framework.
Some or all of the above mentioned activities might also be done in practice as part of the strategy and roadmapping activities. However, it is still good to recognize this as a separate step.
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