Over most of my adult life I considered the study of history to be mostly without value. Since every pursuit has an opportunity cost, the study of history was always secondary to something more practical such as the study of engineering, medicine, a trade, programming, etc.
History according to educators was always a chronologically ordered sequence of events over a geographic area. You took a class on the American Revolution, or saw a documentary on the Roman empire, or read a book on the scramble for Africa. History was just a sequence of data describing largely public or documented events. Even with all the available data it was often lacking in causality. Why did a given policy change happen at the time that it did? At times the answers are known, often they are not. Consequential choices are made, and we are left to speculate as to why. The real drivers of many historical events, such as the private experiences, communications, and thoughts of elites (those in control of strategic resources or institutions), could never truly be known. In this sense history is the study of data, and the data is incomplete.
My thoughts eventually changed as I considered how one might acquire a better understanding of phenomena with historical precedent. For example, you might wonder what causes the rise and fall of empires. It will not be enough to study one empire. You should instead study the British Empire, Roman Empire, Mongol Empire, and Ottoman Empire, etc. and find trends. Maybe you are interested in something more practical like how modern banking crises unfold. I am more interested in the structure of scientific and technological revolutions, so I would be more interested in the history of science, the industrial revolution, the history of silicon valley, and the history of modern technology disruption. What I’m describing is probably called comparative history.
In a sense what changed my view of the practicality of history was a change in how I perceived it: data vs insights. I view a single historical period as just data. It’s hard to be confident in any trends when you only have a single historical period to extrapolate from. Everything about the past was different and maybe the way history unfolded was just a product of the legal, technological, political, etc. situation of the times. I view multiple historical periods as enough from which to draw inferences. If you see a trend, there is a much stronger case to make it represents something deeper and lasting about human psychology and politics at scale.
I am not sure why history is not marketed in this way, since it just seems much more practical. Focusing on studying narrow time periods in the hopes of maybe providing cause-effect links between successive historical events to me does not sound achievable. History largely relies on public, but not private information, and so will lack the ability to truly link cause and effect of why key decision makers made certain choices. But studying multiple areas of history to determine trends seems eminently reasonable. There is now no need to understand this unknowable cause-effect chain but rather the focus becomes what trends persist despite completely different period of history that only share the constant of human psychology.