"A common project-triangle model places quality at the center of time, cost, and scope constraints."
Microsoft's project guidance presents time, money, and scope as the three constraints and quality as a fourth element at the center that is affected by changes to them. + Estimated publication year. The Microsoft article used an Office Project 2007-era URL (HA010211801033) and was cited online by October 17, 2008. The current Microsoft Support page does not display an original publication date.
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