Bootstrapping a side project into a profitable seven-figure business

The validation piece I don't understand. From first sale to first dip to each peak and fall when was the validation reached? First sale, 1k revenue?

You can find 5 users who will pay but that doesn't validate a million a month.

What does product validation mean here.

I only have a product that makes $6k per month, but from my point of view, the validation is how many paying users sign up per day. Even one per day can add up. Hope this helps.