Most alert fatigue comes from alerts that should never have been sent. Hyperping cuts them at the source: a single failed check never alerts anyone, because the other regions recheck at once and an outage opens only if they fail too. On top of that, grouped alerts turn monitors failing together into one alert, alert delays ignore blips shorter than the time you set, and maintenance windows silence planned work.
More than one or two pages per on-call shift outside working hours is a sign to tune. In working hours, every alert should still lead to someone doing something.
No, but one leads to the other. Alert fatigue is about attention: people stop reacting. Burnout is about the people: frequent night pages over months drive engineers out of the rotation, or out of the company.
An alert for a problem that isn't there, such as a check that failed because of the monitoring network rather than your service. See how to reduce false positives.