Nothing is as good as seeing for yourself. When you're the leader, you need to go and look.
A friend was once given the mission of installing a temporary bridge over a stream. After a couple of days of planning and coordination, he arrived at the site with a platoon of Combat Engineers, several truck-loads of Bailey Bridge sections, and supporting medics, only to discover there was already a bridge there.
Things are never as you remember them, and they never match the impression you form from a report. The only way for you to really know is to put your eyes on it. Especially if there's a measurement or data point important to a plan, go make sure.
A couple of quick gut-checks: Is there anyplace under your supervision that you haven't visited in a week? When was the last time you looked at every piece of equipment you're responsible for? Do you ever walk around the property and evaluate the cleanliness and maintenance of the grounds and buildings?
We get so busy with our spreadsheets and e-mails and meetings that it's hard to get away from the office. It's easy to go a while without actually getting to where the action is, especially if the action is someplace hot and dirty. Even worse is if you're responsible for a remote location.
Bottom line: You cannot effectively manage what you never look at. In effect, you're allowing someone else to manage that resource, because you decide based on what they tell you.
So go look. I guarantee that each time you do, you'll find a part of the process that's drifted from optimum, or some housekeeping that isn't getting done. You'll also find some good ideas that got implemented and talk to some good employees who will lift you up. And you'll know, for sure, what's going on out there.
Besides, it's a lot more fun than sitting at a desk.