Volatility in the Work Environment

Work environments fall into two broad categories based on their degree of volatility:

Constant—Deviation from a predictable, established pattern of work is unlikely. For example, a job that involves tabulating the results of questionnaires every day tends to be constant.
Dynamic—The work pattern is so variable that a sequence of operations is unlikely to be repeated frequently. For example, a customer service role, in which the work flow can be dramatically affected by a phone call, is dynamic.

The dialogs designed to support a particular work environment should reflect its degree of volatility.

A constant work environment requires a highly structured dialog in which the system guides the user through the work pattern.

A dynamic work environment requires a loosely structured dialog in which the user directs the system based on shifting priorities.

A highly structured dialog tends to exhibit the following characteristics:

It allows the user limited control because the system determines the sequence of actions.
It uses few menus.

A loosely structured dialog has the following characteristics:

It allows the user great flexibility in switching between procedures because the sequence of actions is largely unpredictable.
It may use a number of menus to simplify navigation among procedures.
It may use function keys and short command synonyms (usually single characters) to provide quick access to many procedures.