Steps to reproduce:
a.) Create a summary alert that is based on two or more simple alerts and set to "all". For the danger and/or warning thresholds, the number of "periods over threshold" and number of "observed" periods have both been set to 1.
b.) On one of the simple alerts, produce data that would cross the danger or warning threshold. However the warning/danger thresholds are not crossed on the other simple alerts.
c.) Intermittently, it is observed that not only that simple alert has been triggered, but the summary alert has also been triggered.
It is possible that the number of "periods over threshold" and number of "observed" periods have been set to 1 and not all simple alerts have returned data to the summary alert yet, and thus creating intermittent issue erroneously triggering the summary alert. Please increase these two values for a longer period observation/evaluation period.