If the company deliberately misleads potential employees it knows it will have morale and productivity problems after people are hired. Nobody wins by deceit. When I think of how intentions meet up with realities, I'm reminded of the story of a person who hired on with a new company. Unfortunately, the new employee's spouse developed medical problems the next year and they had to move away. The person quit the job.
Uncontrollable situations happen to companies just as they do to individuals.
Start-ups are times of visions and promises. That is the nature of start-ups. Everyone needs to work hard to try to make those visions come true. Most of them will. Some of them won't.