Glory
"Estou magnífico!"
Congratulating your own reflection is no longer reserved for public speakers, NFL players, and freaky girls on YouTube. This job is all about glory, personal satisfaction, and a sense of accomplishment. You might as well enjoy telling yourself you're wonderful in the morning. It's probably true, and no one else is likely to do you the honors.
Seriously though, there's nothing better than watching your students grasp concepts, maneuver through new material, and grow their minds. Maybe someday they'll be negotiating the terms for a new green energy plant in Chinese, or encouraging trade relations in Latin America, or maybe simply learning to appreciate and value their Mexican neighbors.
In the end, your students' triumphs will be your own. When they earn an A, when they finally learn how to pronounce a word properly, when they show cultural sensitivity to an exchange student - the victory is yours. What could possibly give you more pride?
You'll have a unique ability to influence and enrich their lives, and you'll get to see the results. Maybe it won't always be a test score or something that reflects directly on you, but the surest thing is that you'll make a big difference to some of your students. Perhaps years later, when you're old and bed-ridden, they'll come and thank you for lighting a spark of curiosity inside of them.