Musts should be measurable. A must will determine whether or not a solution is selected for implementation. If a possible solution does not meet all must criteria, it will not be considered further. Wants Criteria the solution should meet in order to be the best choice. Wants can be measurable or subjective.
Wants determine the priority of the solutions.
The more want statements that are met by the solution, the better the solution. There is no ideal number of criteria, but a large number of criteria will take more time to analyze. Analyze and discuss each solution individually. Decide whether the solution meets each criterion. The team now has a prioritized list of key solutions to further develop.