It prevents burnout
In general, the more often you raid, the faster you'll progress, so it's tempting for guilds to want to run multiple times each week. But that puts a real strain on members, who can't always commit to every raid and who end up getting tired of raiding in general over time. Eventually, guilds run into a situation where they're shorthanded because more and more members simply aren't logging in or are coming up with creative ways to skip raiding.
If you have a surplus of raiders, it's possible for a guild to consistently raid and give players the opportunity to take a night off here and there. But if you're going to successfully rotate players in and out, it's important to close the gap between the best raiders and those who aren't as productive. Otherwise, you run the risk of bringing in a raid force that's too weak to handle the content when you give the top players the night off. If you can narrow that gap, though, you'll be able to prevent burnout, and you'll have a stronger core of players as well.
It helps with attrition
Every guild experiences attrition, and it's unavoidable that even the most loyal players will leave the game, and the guild, for periods of time. When that happens, guilds run the risk of falling backwards in progression because the raid force is too weak. If you're running raids with a surplus and rotating players in, you won't be affected by attrition as much, so you can avoid the rebuilding process when you do lose members. It essentially buys you time to recruit, shore up the roster, and get those new members up to speed without losing momentum.
It helps you fit targeted needs
Some members might need specific upgrades, and those needs don't always overlap. With a surplus raid force, you can prioritize and knock out those gear gaps without having to drag members along who might have done the content many times and don't need anything from the raid. It's hard to go into farm mode with a raid zone and do it enough to get everyone what they need. Burnout strikes, and a guild leader has to make the tough decision of leaving a zone even though there are some folks that haven't gotten all the upgrades they could use. That's a problem because it's part of the reason the gap between the best and weakest raiders exists. If you run with a surplus of raiders, you can stay on farm mode a little longer and gear your members up a little better.
Find a balance
The hardest thing is to find the balance between having extra raiders without super-sizing the roster so much that you become too bloated. While some players will appreciate a night off here and there, they probably won't appreciate having to sit out over and over. If you have too large a raid force, and players get frustrated with the scenario of too large a bench, it will potentially lead to drama. You'll also probably end up losing so many players that you'll not only eradicate your bench but be operating at a net loss.
A well-rounded guild
Whether you raid with a surplus or not, if you're in it for the long haul, it's important to make your guild be about more than just raiding. The best part about guilds is the team atmosphere that develops over time, and while raids are a great venue for that camaraderie, they're not the only one. Give your members a chance to bond in other ways, whether it's through social events, dungeon runs, or a "name that '80s song" contest in Vent. If you include many activities as part of guild life, it de-emphasizes raiding and reduces the competition among players to be in the raid all the time. The bench, as a result, isn't something that's looked down upon but a natural part of raiding over the long term.
The other benefit to having a more well-rounded guild is that it makes everyone feel like part of the team. Your guild might have players who don't like to raid, might be lone wolves, or feel excluded from the clique. By making your guild more of a home, all the members feel like part of the team, they're more likely to stick around, and they'll have the freedom to find their own fun as well as contribute to overall guild goals.
In short, if you raid, you'll really have to maintain a surplus of players in order to form a viable force and navigate the real life obligations that prevent players from being on for every raid. You can't force people to raid, and in reality, you shouldn't. Given that fact, you can raid, have a bench, and prevent frustration and drama that could result. It might get tricky at times trying to rotate players in and still keep a solid force for each raid, but if you can, it will benefit the guild over the long term.
Do you have a guild problem that you just can't seem to resolve? Have a guild issue that you'd like to discuss? Every week, Karen Bryan takes on reader questions about guild management right here in The Guild Counsel column. She'll offer advice, give practical tips, and even provide a shoulder to lean on for those who are taking up the challenging task of running a guild.