A workflow pattern is an ordering of tasks, or sequences of tasks. Workflow patterns are shaped by two parameters: how tasks relate to one another in the workflow process and what opportunities exist to execute decisions during the workflow process. Workflow patterns are often illustrated visually as a series of logical choices defined and placed within a flow chart. The work task may be accomplished by automation, or workers may perform the task manually. The logical process of the flow is the same in either case.
In a sequential workflow pattern, the next step cannot be completed until the existing task is moved forward in a sequential order. A sequential workflow pattern can be illustrated as A to B to C. As a worker fulfills a task, that worker may hand off the completed task to another worker. The next worker in line either completes another step in the process, or sends the work on to the next stage of production.
If the worker's choices are restricted to just one, the workflow pattern is called “exclusive,” as it is an implicit termination. The worker can only proceed from A to B and no further. When more than one choice is available to the worker, then the process is referred to as an “explicit choice pattern.” In this scenario, the task could go from A to B or C or D, and so on. The process may also go in the other direction from A or B or C to D.
A parallel workflow pattern occurs when multiple workers fulfill tasks at the same time, without requiring that a decision be made. For example, there might be one worker who moves a stack of material on to a group of workers in the assembly line. All of these workers process those individual items within that stack in a simultaneous fashion, which would be A to B and C. In another example of a parallel workflow, more than one worker may complete a task, which is then routed to just one worker in the next step in the workflow. An illustration of this parallel workflow pattern would be A and B to C.
If the worker completes a step that now requires a logical decision to be executed, it becomes a parallel split. This can be illustrated as A to B or C, or A or B to C. In a workflow, tasks may be split into new workflow patterns, and then be recombined further on in the assembly process. The pattern might be A to B and C and then back to A, as the workflow stream splits and comes back together once more.