When working with viewpoints some get more attention than others. Some might even be totally ignored. This might work out well but you expose yourselves to higher risks. Thus: looking at your project from the listed viewpoints helps a lot to identify blind spots in your project management.
If you are working on a project on your own it's clear: you're in charge of looking at all viewpoints by yourself. If you work in a team: split the viewpoints among the team members and make sure all viewpoints are covered and the lead for each viewpoint is clearly defined.
With the team: define the minimal scope of each viewpoint. The facilitation role can help. The person is selected from within the members of the organizing team.
Make sure you and the champ agree on
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