Referees and umpires usually are only noticed when they make the wrong call. When they do their job properly, you only focus on the players and the action on the field.
Another saying I ran across: Buddhists call housework "invisible work" because you only notice it when it's not done.
I don't know if your job or position is one that's out in front and very visible or if you're hard at work behind the scenes. But, I'm willing to bet that it's no less important either way. Doing your work well is important because even if you think no one notices, I'll bet someone would notice if it were left undone.
Work hard, even if you think no one is watching. Because eventually, someone will be.