What is culture? In the broad sense, it's a way of life. More specifically, it's a basket of shared behaviors that determine how we solve problems, define success, and treat each other.
Culture is important. It has been proven critical to socioeconomic success, at every level, from the extremely large group to the individual (although at the individual scale, we call it character). For example, in the corporate world, most successful CEOs will tell you the same thing: culture is everything.
So, if it's so important, why don't we talk about culture more?
It isn't easy to quantify. It's not easy for bureaucrats to dictate or markets to measure.
Fortunately, there is a way to understand it a bit better. Culture is important because it plays a critical role in personal and group decision making. More specifically, it drives the "orientation" step of John Boyd's decision making model, the OODA (observe, orient, decide, act) loop.
Orientation is different than the other steps in decision making. It's a gut check. A check of core values. It is a synthesis of everything you've learned as it applies to the problem you face. This makes it squishy and holistic. It's the step that Einstein so elegantly referred to in this quote:
If I had only one hour to save the world, I would spend fifty-five minutes defining the problem, and only five minutes finding the solution.
Unlike orientation, the other steps (observe, decide, act) used in decision making are largely mechanistic, analytic and quantitative. To improve these other steps, you speed them up (i.e. computers), increase their fidelity (accuracy without error), and widen their scope (more data).
In contrast, culture is how human beings have learned to speed up orientation in a dependable way.
Culture can provide any individual, organization, or country with the outlook needed to successfully orient problems repeatedly and without hesitation.
Here's an example:
Some business cultures place a high value on treating the counterparty in a transaction with respect and dignity. In those cultures, it's important that every business transaction is a win-win, where both sides are better off for doing business together, regardless of the contractual details.
In other business cultures, business transactions are highly competitive. In those cultures, it's important to win every business transaction and contractual details are used as a weapon to bludgeon the counterparty into submission.
See the difference in approach due to culture?
What should also be obvious from this example is that cultures differ. They can be wildly different.
They aren't equally effective, the usually don't mix well, and some can be toxic.
PS: John Boyd developed the OODA loop to figure out how to win conflicts. He postulated, correctly, that successful decision making is the most important factor in survival -- from simple organisms surviving evolutionary pressures in primordial pools to winning wars on modern battlefields. Therefore, success in any conflict was largely due to faster, better decision making. The faster you can make good decisions, the faster you can iterate to success.