For late-stage companies, a common mistake would be not rolling out an executive team early enough.
If you are a first-time founder in particular, or if you have never run a team to scale, your instincts are often to hire very smart individual contributors and you don’t really understand the leverage of having a great executive in place.
That’s why often when you see second-time founders start a company and among their first 15 people, they have three or four VPs and a CXO, and often, as a first-time founder, you ask why does this person need all these executives, it’s only a 15-person company, but then after you have been through scaling a team and company rapidly once yourself, you realize the enormous leverage you get by building out an executive team.