How do you know when you've validated enough? (Most founders never figure this out)

— People assume that you have a good segmentation in terms of customers and I think one of the best ways to segment your customers is by looking at not at their demographic, psychographic, or anything like that, but looking into their circumstances. What is happening in their life that causes them to do a certain job and what they employ to get it done. And so, if you look and nail your customer segments or nail them in in a good enough way, then when you start doing like customer interviews, the moment to stop is the moment when you start hearing pretty much the same thing. So, if you don't start hearing similar things after, let's say, 15 or 20 interview, the most probable reason for that is because the people that you talk with are not part of one in the same customer segment. And so, this is a moment where you can say, "Okay, let's look at what we have, look for subclusters, and then change the definition of split it, merge it, whatever the data is showing. If you hear 500 different problems, you either have a broad too broad customer segment or the challenge is not so big. A guidance that is not um rooted in anything but experience, like empirical uh number that you will see in your practices between 12 and 20 interviews. So, when you have like your customer segment well defined, and I told you how you ensure that, then in 12, 15, 20 interviews at a given point in time, you should be able to see one in the same patterns. And because everything changes, you have to have a continuous process that explores that.