Professors can lead to the first sale
For science-based startups, one of the largest challenges is finding their first customer. Ideally a customer who is committed to buying even before seeing the product.
Startups inherently lack credibility because they haven't done what they are doing before (23-12-13_Trust for startups). But the founders can have credibility because of their previous experience. That's why I believe the role of a professors who becomes co-founder (Professors can enable scipreneurs) can be to enable the first sale of an instrument (Product market fit for scientific instrumentation).
Leveraging their network, it is possible to create the opportunity that leads to a first customer interested in what the company is producing, even if it's via a more 'academic' partnership than a traditional purchase channel.