Someone (a mark?) getting through the filtering (sales?) funnel's first stage is a strong signal for what? That someone period is interested in your product/ser

Someone (a mark?) getting through the filtering (sales?) funnel's first stage is a strong signal for what? That someone period is interested in your product/service you're offering? Or that this particular person, the one who reaches the second stage of the funnel, is a possible lead (or exactly a lead)? Likely the latter. Because you can skip the scientific/investigative validation of the hypothesis that there is someone that wants what you offer/sell/provide. That is, you should assume that there is someone out there (a small number of people at least, really) that wants to pay you for what you provide. I know this goes against common startup wisdom. But there's a massive cold outreach campaign type that needs to function and it needs to function with some confident assumptions within its technological engineering implementation. I guess. I'm just speculating on some theoretical startup founding that doesn't suck.