If you configure maximum variances for the shift start time, the scheduling engine tries to find a set of daily schedules that meets the specified constraint. If the scheduling engine cannot find a match, it ignores this constraint.

Maximum shift start time variance example

Assume you have two shifts with completely non-overlapping start windows. In this case, if you create a single maximum shift start time variance for the entire week, the scheduling engine is unlikely to select it. This conflict occurs because the variance duration must be large enough to overlap both of the shift start windows. The two variances is a more likely choice, and also allows for more variance across Saturday and Sunday compared with the weekdays.