Being a public company adds, in my experience, about a million dollars a year to your expenses in terms of managing the SEC filings and the accounting overhead for keeping compliant with all the Sarbanes–Oxley overhead and audit controls in addition to all the stuff that goes into filing your SEC reports. One. Million. Dollars. Minimum. Much more if you’re complicated in any way.
Being public also completely changes the way in which your company operates. As a private company, the CEO with advice and consent of the board sets direction and can do things that look wildly risky but have a big return. As a public company, the scrutiny and shareholder accountability are completely different, and you’re now operating the company trying to manage to a quarter-over-quarter horizon instead of being able to take a five year view.
If you’re not equipped to deal with that, it’ll drive you insane.
That is one of the reasons that relatively speaking there are so few publicly traded companies to successful private companies. People who are the business of creating massive success prefer to be able to call their own shots.