If a user wants additional time to finish a job, let him use "Extra work" column

In the bundled HTML help (which launches when we press F1 in ProjeQtor, this page states that-

By default : Left = Assigned - Real
Left work should be re-estimated by the resource.

These are inconsistent statements, because the equation makes the Assigned and Real as independent variables and Left as dependent variable.
In that case the resource should not be able to change the Left variable.

To solve this issue, let us use a a third variable called "Extra work".
Then-

Left = Assigned - Real + extra work

The "extra" implies that this was not planned beforehand.

This has another advantage: If the resource is able to simply revise the Left figure, it is like moving the goalpost: The delay gets hidden.
But if the resource is asked to specify the specific amount of extra hours, it is held under limelight.
Also, while PM has to justify the Assigned hours, the resource has to justify the extra time he needs.

The negative value is not a big deal.

It is similar to the "delay" value in a FS dependency: Sometimes you may want a negative value there also (thus building an overlap). Just as we have not minded such possibility there, we should not mind an occasional negative value, as long as the majority case is nicely addressed.

BTW in accountancy also, if there is a loss, it is still written in the "profit" column, but in parenthesis (they never use a negative sign). Thus each profession has its own convention.

And thanks to Hofstadter's law, most of the time it would be a positive value only!

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@Difficulty in expressing "extra"

Well, first of all, it is very natural for a resource to say that I am left with 5 days, but I need 4 days extra".
It's a simple math that we do in our mind subconsciously: The resource needs 9 days in all.
No big deal.

But the current system hides the fact that there are two Lefts now!

• One Left is the time left according to the original assignment (what the PM takes for granted).
• The second Left is what the resource has decided for himself.

But ProjeQtor shows only the second Left: The original Left is lost!!
Unless the PM keeps saving baselines, he cannot predict when any of the tasks will get extended.
If you look at any views of the projects, such extensions are impossible to spot at a glance.
Practically, the PM loses control on his project.

On the other hand, any value in the "extra" field catches his eye, and these are all delays (99% of the time), cause for concern.

As regards psychology, please consider the influence of cultural/business constraints.

Take India (strictly as an example).

A typical Indian way is "top-down". Here, resources do not enjoy equality with their bosses.
(see comparison of cultures between between India and France)

India is a global favorite for software development. But to please the global clients (against stiff competition), Indian vendors commit tight deadlines and low margins. They simply cannot afford to let the project get delayed unpredictably.

This prevents them from allowing their resources a free hand to add delays.

If the PM does not want any delays (especially in the MCP tasks), ProjeQtor must not encourage the resources to add delays.

Moreover, ProjeQtor keeps the PM totally unaware of the delays being added without warning. This is a nightmare for the business!

The psychological angle can be handled best if the delay is already negotiated with the boss.
Then the resource can fill that new value without any trepidation.

In fact, no designed feature can override the business compulsion and cultural bounds.

For example, ProjeQtor does not allow anyone to work beyond 8 hours per day. But slow workers would have to work more hours to catch up. And yet they may want to declare the same 8 hours of real work, to hide their own inefficiency. (If they enter the real number of hours they put in, their billing may exceed the budget, which may put their job in jeopardy!)

Thus the resources will cheat with ProjeQtor's auto-leveling feature for self-preservation!