We had a discussion in my guild yesterday. We are currently having some attendance issues, which meant that in the past week we couldn't go mythic because we would have had to pug too many people (6 yesterday). Instead we did other things, but it's just annoying, since we do have a 21 man roster. My solution was: recruit more, get a decent bench for if people can't make the raid or fuck up a lot etc, and if we do have more people online then spots in the raid, we rotate them.
I got told that situation was not viable for our group (3/10M could have been 4 or maybe 5 if we didn't have the attendance issues), because people who would be on the bench would simply not be online for that day and if anyone else then had to go or be unavailable at the last moment, we'd still be in trouble. According to them the only way to solve attendance when having a bench would be a DKP/EPGP loot system, to reward people for being on the bench. At the moment our loot system is simply rolling for loot MS>OS where we expect people to yield minor upgrade winning rolls if it's a major upgrade for someone else. That system works fine for us at the moment. I really dislike points for loot systems, so I would really prefer not to go that way.
We are not hardcore, and have no attendency requirement (although not being there regularly does get you a talk and not being there ever does get you demoted) but we would like to progress further and it's not going to happen like this.
So how do other guilds do this? Do you have a bench to ensure raids get to go on despite absences? And how do you keep benched people motivated to show up, even though they know in advance they will be benched? Benching per evening or boss? EPGP/DKP point bonuses? Loot council?