Prescribed work and actual work

The job description, the procedure and the operating instructions describe what is expected. Observing the activity describes something else: adjustments, shortcuts, added checks, incidents dealt with without appearing anywhere. Both descriptions are accurate, but they do not bear on the same object.

The distinction between the task, that is, what is prescribed, and the activity, that is, what is actually accomplished, has structured French-language ergonomics for several decades. Jacques Leplat gave it a formulation that has become classic, later taken up by work psychology.

This distinction is not to be confused with the one Taylor drew between design and execution. For him, the gap was an imperfection to be reduced by more detailed prescription; for ergonomics, it is a permanent given, which signals what execution really requires.

The gap is not interpreted as disobedience. A prescription cannot anticipate every situation: materials vary, tools wear out, requests arrive in an unforeseen order. Bridging the gap requires a work of interpretation that the prescription itself does not describe.

The work-to-rule provides a demonstration by reductio ad absurdum. Applying the regulations strictly and exclusively is often enough to slow an activity down considerably, which shows that its ordinary functioning relies on initiatives that nobody formally asked for.

Activity analysis, developed notably around Alain Wisner at the Conservatoire national des arts et métiers, a Paris institution for adult and vocational higher education, proceeds through on-site observation and through interviews in which people comment on what they are doing. It seeks to reconstruct the reasons for choices, not to check their compliance.

This approach produces results that indicators do not see, such as the collective regulation through which a team shares out difficulties. On the other hand, it requires time and access to the field, which limits its spread beyond prevention interventions.

Work in the clinic of activity, associated with Yves Clot, describes what it calls impeded work: the situation in which people cannot manage to do what they consider necessary to do their work well. The mismatch with the prescription then becomes a source of wear.

Conversely, the room for interpretation left by the prescription is also what makes it possible to cope with the unexpected. Reducing the gap by making instructions more detailed can thus remove a resource as much as a risk, depending on the situation.

The open question concerns the place to give this informal knowledge. Some approaches seek to integrate it into revised procedures, others argue that formalising it would freeze it and make it lose what makes it useful.

Both positions rest on documented cases. The disagreement lies less in the facts than in how prescription is conceived: as a framework to be constantly supplemented, or as a description that ought to be made exhaustive.