Atkinson, Roger: Project management – cost, time and quality, two best guesses and a phenomenon, its time to accept other success criterin; in: International Journal of Project Management, Vol. 17 (1999), No. 6, pp. 337-342.
Once I spent some hours discussing with colleagues what the magic triangle might be. PMI says it is Time-Cost-Scope and Quality is a product of these three. My colleague argued it should be Time-Cost-Quality since Quality is defined as meeting or exceeding the expectations of the customer, which includes that the customer gets what he asked for, aka the scope.
Similarly Atkinson argues that this is only asking the question of the project is ‚Doing it right‘, which automatically focuses mainly on the delivery system. Thus leaving huge gaps in the ‚Getting it right‘ part unanswered. Which leads, as many IT project examples show, to a nice but unusable/unwanted/unaccepted piece of software. In order to get it right by doing it right Atkinson proposes the ‚Square Route‘ of success criteria – (1) The Time-Cost-Quality-Triangle, (2) The Information System itself, (3) Organisational benefits, and (4) Stakeholder/community benefits.