As a guild ages, the chances you can avoid dealing with some kind of drama related issue goes down to zero. The cause of drama is people. Every guild has people in it. Therefore, every guild has drama. And drama is, usually, what leads to burning out of officers and guild leaders. Every dispute, argument, disagreement, mistake, and accident can end up draining the officers of their will to play. At some point, an officer or guild leader will have defense mechanisms that will kick in to try and keep some sanity. Maybe they stop logging in as often as they used to. Maybe they start lashing out at people who drop problems at their feet. Or, even worse, maybe they just stop caring what happens. Classic burnout.
People expect more from their government over time. This is true in the real world, and it's true in guilds. Not a day goes by where some group isn't on the news demanding or begging for some government (theirs or another) to step in and help do more. "Come here! Fix this!" Few people look outside their own door and say, "I guess I'll have to help fix this problem." I see this same mentality echoed in my guild. The small number who want to help make the guild better are quickly promoted and put to work. The vast majority want to know why there isn't a Karazhan raid scheduled this week, or why we don't have more tanks in the guild. It's never enough. It's not long before the officers feel like everything they do is just drops of water on a huge fire of demand. That can be psychologically overwhelming, especially when all your time spent managing and coordinating are not bringing in anything positive ... much less a paycheck. I can not seriously remember the last time I heard someone tell a raid leader how much they appreciated their work after running a raid. I see a lot of "grats" and "now what?", but not a lot of "Thank you for running this raid!" It wears the leader down over time. If you every ask yourself why you bother, you're getting burnt out.
I tell you players who are part of a guild to not take your officers, raid leaders, and guild leaders for granted. Tell them that you appreciate their hard work and effort. And then ask them how you can help. They might not need the help right now, but just being willing to do a little bit to help keep the guild running will help. The success of a guild rests in the hands of the entire guild, but usually those people are standing on the shoulders and backs of a very small number of people.