It sounds like you are describing the Silicon Valley ideal, but things like "finding a good business to start" are very much a traditional approach, and I am confident they will teach you about how to do market research to this end in business schools.
Is it a traditional approach? I've met a lot of entrepreneurs and small business owners, and I have heard of almost nobody starting from "I have started a business, now what should we do" being successful. Bezos arguably took that approach, but that story gets told so much precisely because it was unusual. More often it turns out like Webvan, where the lack of deep domain knowledge means making noob mistakes that kill the business.
And I'm not sure business schools are a big help here. The vast majority of MBAs end up joining mid-sized to large existing companies as high flyers, and I think the curriculum aims to support that.
In the US this is precisely the traditional approach. The country was built by immigrants who would arrive in an area -- San Francisco or New York for example -- decide that if they didn't want to work in a sweat shop they would have to start a business, then look around to see what their neighborhood needed, and build it. Laundromat, restaurant, feed store, etc.
They didn't need to be intrigued by a problem or have a background that set them up to solve one. They decided to start a business and began by figuring out in what way their region was underserved, then built something to fill the gap. Voila.
There's no obvious reason this approach couldn't work in tech as well.
One, I think starting another instance of a well-known kind of business is very different than creating a new product, especially when one has used that kind of business a lot. So even if what you say were true, I don't think it would be relevant to, "I've started a business, what kind of product should we make."
But two, I'd like to see some evidence that people really did entirely arbitrary things based on demand, without relation to other factors. If we look at a well-known example, the way Indian-Americans have dominated the motel industry, there's pretty clear evidence that wasn't just driven by looking around the neighborhood to see what was needed. E.g.: https://blogs.wsj.com/indiarealtime/2012/06/11/why-indian-am...
Sure, but they were literally neighbors back then. The world has changed since then and we don’t necessarily have neighbors from a completely different walk of life. Additionally, non-tech work has a different domain of deep knowledge necessary to properly serve industry knowledgeably.
Just because your neighbors a welder, doesn’t mean you can whip out a materials inventory app for welders everywhere.
A common approach is people believing they can be their own bosses. Not so much about business opportunity or an itch to scratch.
Anyway, why speculate? It's easy to find online articles and research showing why people have started their businesses, or the reasons why people would want to start one but haven't yet. Truth is that it's all the above and more.
> I've met a lot of entrepreneurs and small business owners, and I have heard of almost nobody starting from "I have started a business, now what should we do" being successful.
None of them told you that this is how they went about it, because it's a bad story.
You're making a mistake if you're thinking of Bezos as an example in the context of small business owners. Actually, you can probably just rule out Bezos and any of the other FAANG companies as crazy exceptions.
Outside of tech, the standard entrepreneurship story is "I want to be my own boss; hmm, maybe I'll franchise a McDonald's".
It's only in tech that we end up equating entrepreneurship with things like innovation, solving brand new problems, etc. That's because the most successful tech entrepreneurs are the ones that did innovation (for the most part).
Well, the whole theory of a franchise is that it reduces all risk because the product has already been figured out. And franchising didn't really become popular until after WWII, so I'd have a hard time calling it "traditional".
And just to be clear, I'm not thinking of Bezos as an example of small business owners. He's just the only person I've ever heard of who successfully said, "I'm starting a business. I wonder what it should sell?" As you say, I think he's an enormous outlier.
As far as I know, he had a business model involving an emerging technology, and wanted to select a product that would be most successful with it. He felt books was that product. He's said as much in interviews.
