That's not unusual at all. A lecture at Harvard Business School about startup IPO mentioned that first time founder CEO and first time board member get more oft

That's not unusual at all. A lecture at Harvard Business School about startup IPO mentioned that first time founder CEO and first time board member get more often then not replaced. Read about the business case of Lewis Cirne who got replaced at his first company Wily, and founded later New Relic with many lessons learned.