The drive to find purpose, to fulfill ambition, is a misdirection forcing you to disconnect from reality.
Sam Harris says ambition and purpose are imaginary friends; there is no reason that reality is insufficient.
This is true, but also privileged nonsense. Having the ambition to achieve lands you in a place soft enough to consider purpose, where before it was clear: survival. Many people are hip-deep in reality (aka survival), from which our ambition can drag us free.
The irony Harris brings to light is that achieving the comfort that allows us to consider "purpose" is to overcome survival, that is, to escape the nagging confrontations of reality. Once free (free of reality, free to consider purpose), we should turn off our ambition to return to reality.
Yet overcoming requires such persistent effort that humans are conditioned and are dreadfully afraid to return to the state of survival. It is not that Harris is wrong -we should reconnect with reality and drop illusions- but it requires a mad overcoming or padded life before such returns to reality are wise.