For developer tools and B2B SaaS, what actually matters to VCs at pre-seed? I will not promote

I'm curious to hear from founders who have raised pre-seed rounds, investors, and people who have been close to the process. When you're building a developer tool or B2B SaaS product, what do VCs actually care about most at the pre-seed stage? How much weight do they put on traction (active users, retention, paying customers, or early interest) versus market size, technical differentiation, founder-market fit, and distribution? For a product starting with a narrow use case, how important is it to demonstrate a credible path toward a much larger market? And for infrastructure or developer tools, where adoption can take time, what kind of customer validation is meaningful: design partners, LOIs, interviews, willingness to pay, or consistent usage? I'm also interested in what investors expect founders to have figured out before raising. Do they need a repeatable acquisition channel and clear evidence of willingness to pay, or can a strong technical product, a specific problem, and early customer validation be enough? If you've raised or evaluated pre-seed rounds, what evidence made you take a company seriously? And what signals do early founders tend to overestimate? Concrete examples would be especially helpful.