Recently I had a client give me an idea for a new product he had been thinking of and then ask me for a Gantt Chart (Gantt Charts illustrate the start and finish dates of the terminal elements and summary elements of a project) for the project. I tried to explain that creating such a document would not lead to anything real and I was really getting nowhere in my attempt to explain the specific reasons.
This particular client manufactured capital equipment and relies heavily on the use of Gantt Charts for planning and scheduling. It seems reasonable to believe that product development should be able to do the same. After the call, I realized that the reason Gantt Charts do not work for product development is that product development is a series of decisions, not a series of tasks.
True, a Gantt Chart will allow you to connect dependent tasks, but product development decisions change (or define) the actual task that needs to be done; that is, you do not know the next task until a decision is made, and it’s the decisions that have the dependence, not the tasks themselves. That being said, this is largely true in the Requirements and Conceptual design phases of the project, and less true in the detail design phase.
Once a good Conceptual Design and Drawing Tree are completed, a Gantt Chart works well for planning the Detail Design phase of the project. The point is, in product development it is important to focus on making decisions as well as tasks.
To be effective, you need to make good decisions and make them at the right time. The more diverse the team, the better the decision.