My company sends a weekly mailing to a particular group of contacts. The week of August 9th our stats showed 287 recipients in this group, two of these emails soft bounced, and we had no opt-outs. The following week the number of recipients was listed as 279, and several people confirmed that they did not receive that week's mailing. Nobody in our office modified the members of the group in the meantime (or at least won't admit to it!) Is there another reason that we would have lost 8 random group members?