Road atlas, paper airlines ticket and checkbook balance calculator all are unable to automatically update the underlying information to preserve the correctness of the information that the human read.

The design of the older generation project management tools is similar to the checkbook balance calculator to simplify calculations but unable to function like an ATM to track the underlying changes and provide up-to-date information accordingly.

A checkbook balance calculator is merely a personal tool and its shortcoming affects only one person.  But a project management tool is a team ware and its shortcoming affects the team or even entire corporation.  When project team members know the official project information presented by the tool deviates from reality, they would take advantage of the deviation.  This is the same effect as a manager who confuses appearance with reality leading the team.