The Gantt Chart: Already Dead Or Still Alive?

The Gantt Chart: Already Dead Or Still Alive?

Recently, I was confronted with the provoking statement: "Henry Gantt is dead since almost 100 years, and virtually his charts are too." I did not reply, but decided to give this a thought.

The hypothesis that something is considered to be dead automatically implies that it had been alive before. As we are not talking about a person here but about a visualization technique, dead and alive in other words mean that this technique had a value in the past but is regarded as no longer needed nowadays. Hence, it can be worthwhile to lock back into the past when a Gantt chart not only was seen as valuable, but also as revolutionary tool. This may reveal some more insights why it might have died since then.

The environment, for which Henry Laurence Gantt invented his charts, was the production industry and the prime use case was the improvement of managerial decision-making in the scheduling process. The design of the Gantt chart followed the question which information a foreman or supervisor needed to see in order to quickly understand whether a production was on schedule, ahead of time or running late. Gantt introduced the idea to use time and resource usage and no longer quantity as a yardstick for making scheduling decisions, and created various types of charts depending on the individual needs of the production managers. These executives at that time had to manage bottlenecks, were supposed to deal with uncertainty, and needed to cope with all problems resulting from the still high degree of human contribution to industrial production. For this environment, Henry Gantt created a chart that summarized all relevant information at one glance to enable managers making profound scheduling decisions.

In a nutshell, the Gantt chart had been alive when the following characteristics were met: It had to be production environment where decision support for scheduling processes were needed and required context-sensitive information ("for individual needs") at one glance taking into account time and resource usage as crucial determinants.

What has changed since then to declare the Gantt chart dead?

Although we are heading towards the so-called service society, the cumulative net output of the manufacturing industry still counts for more than 25% of the global GDP (source: World Bank). Undoubtedly, this sector still has its relevance. Competition is increasing and many products more and more become a commodity. Both trends drive a margin pressure especially in the manufacturing industry. This allows making the initial assumption that scheduling processes have become even more important, and as such the tools providing decision support for scheduling tasks.

This assumption can be endorsed by three core evidences: First, it seems to be common sense that time is a key success factor for production companies. An underlining evidence for this common sense can derived from looking at common key performance indicators such as time-to-market or production methodologies like just-in-time. This raises the question why a time-focused scheduling tool is regarded as outdated. Second, since the good old days of Henry Gantt the ratio fix costs to variable costs has been becoming more and more fix cost-savvy. This is also and even true for production environments. In fix cost-intensive areas, people typically have to put a high emphasis on the best possible resource usage to make maximum use of the fix cost-driving capacities. Again, the question needs to be raised why a resource-focused visualization to support scheduling decisions should be outdated in such a scenario. Third, one needs to look at decision support itself. The delivery of context-sensitive information has arisen as one candidate for becoming a new paradigm for the design of decision support systems. This becomes even more relevance if one takes the tremendous data growth into account. Henry Gantt intended to create exactly this. His charts were meant as a context-sensitive tool to improve time- and resource-based scheduling decisions. For the third time the question needs to be raised why this is considered as outdated. The opposite seems to be true: For manufacturing companies, there is more need for a Gantt chart than ever before.

Finally and fair enough: many of "the Gantt is dead" advocates come from the project management industry. This specific use case of a Gantt chart has not been analyzed here. The focus here was to prove that the Gantt chart as Henry Gantt invented it, still is alive and needs to be alive in the production industry. I feel, this question has been clearly answered.