If the project was unsuccessful what would possibly happen with that particular project? Should it be deleted?
I would argue against automatic deletion. Maintaining project records for some period of time may be dictated for regulatory reasons (e.g. if you are in pharma or financial industries), corporate record retention policies, and as a general best practice so that you can consult past projects when planning. Give the end user the option for archiving or otherwise saving the project files instead.
If the project meets the deadline and was presented to a client and the client was not satisfied of the outcome. What will happen to that particular project? Should it be re-opened again?
Clearly if your client wasn't happy with your project products then your project wasn't successful.
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A pet peeve of mine is the mania for schedule and budget being the primary measures of success for projects. In some instances this is appropriate that they contribute to your definition of success, but I would argue that delivery of business value for money spent is the key metric. This will also allow you to consider things like product quality, effectiveness of project visioning and requirements gathering, impacts on business risks, etc etc etc.
The challenge is that it takes time and effort post-project to assess business value, whereas adherence to schedule and budget are tantalizingly easy to collect, appear to be objective, and coincide with project end... all of which make it easy to figure out who gets what bonus on their next performance review.
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