One seed startup (where I had our prestigious flagship enterprise customer running with thus-far-perfect uptime in critical production, but we needed a second customer before we could raise), and which was down to a few people, I tried to convince a biz person to let me pitch in on sales.
(Seeing as how, although I dislike doing sales, it was what most needed help right then, or there wouldn't be a business, and I could also use product insight into what actually resonates with customers. And I've done a bit of sales before, and my dad was an engineer-by-training salesperson (osmosis!). My mindset is I don't try to pretend I'm not a nerd. I instead convey that I'm genuinely aligned with their success, I'll listen and understand, and I'll deliver successful solutions like competitors can't.)
Nope, we need a glossy Web site including video. Biz person needs to reformat our security assurances document into a brochure before it can be handed over to prospect's IT for vetting. And biz person needs to introduce me on a customer call as "one of our software engineers" (when I was the only one, working the usual technical cofounder miracles). :)
Like all startups, there were many mistakes, but I think one of the mistakes that time was thinking we had to fake it till we make it, when that undermined our strengths. (Well, slick artifice fit some of our sales prospects, but we didn't land those anyway.)
In hindsight, I think we should've focused on presenting ourselves as an exceptionally skilled and credible team that is 100%+ committed to the pilot project being a success for that particular customer (and for our champions there).
Competitors' salespeople couldn't deliver that, nor fake it very credibly, and there wasn't yet an obvious enterprise CYA alternative (nobody ever got fired for buying IBM).