No Checkin in X Duration includes guests who haven’t made a check-in in the selected time duration but could have made a redemption. For example, the segment below checks for guests who haven't made a check-in in the past 30 days.
NOTE: No Checkin in X Duration, pulls users based on check-ins (regardless of redemptions) ONLY IF they had a check-in before the specified X duration. If they never had any check-in activity before, they would not fall into this segment.
For example, "No check-in in 30 days to today" will look for a user where no check-in was performed in last 30 days, keeping in mind that they will be included only if there is a check-in before 30 days.
If you use LIFETIME as your X duration, then this will include all the guests who have never made a check-in before (regardless of redemptions).