There are a small handful of professions, things like pilot or surgeon, where the purpose of the team is to make the guy leading it perform better. For most of us, it's the other way around. We're worth what they pay us only to the extent that our organizations get more from our teams.
It's worth asking yourself if that's true. If it is, you should be able to point to what it is that your team does better with you around. Some good questions:
What did my people get done today that they couldn't or wouldn't have done if I weren't here?
Is my team any different now than when I took over?
Does my individual work result in some advantage for the organization?
Ideally you can point to something specific, like individual productivity is up 10% because I do this, or I save each producer an hour a day by doing that. Ideally you can express in dollars the difference you make, and ideally that amount is more than you cost.
Most of the time it's not that clear cut, but it's still worth thinking about. Your gut will tell you, after a little thought, if you were a smart buy for your organization. The good news is, if you feel like maybe you weren't, you can change that. After all, few things feel as good as being worth what you're paid.