Look I get it. You're busy or just lazy and you don't feel like explaining why someone won the battle. You just need credits and this battle is fucking obvious who won so why explain?
That's a good question hypothetical person, let me answer that.
Feedback. Feedback is KEY when it comes to improving your skill set. It doesn't matter if you do text, topical or audio feedback is GOLDEN. The only way to improve is to hear negative remarks about your material and better yet, ways to improve on certain sections. If someone doesn't get feedback but continues to win battles they're not going to better themselves, they're going to consistently deliver their mediocre bars thinking they're dropping knowledge.
The problem stems from this lack of awareness. Pretty soon the whole site is stagnant and as a result you've got to battle shitty FaceBook opponents where simple wordplay and extremely played punches reign supreme so even if you drop LetsBeef 2006 type bars you lose because everyone is too stupid to understand your bars tower above everyone else's.
The second point I'd like to make is

see,

do. People have an innate need to follow others. Controversial, stupid, materialistic and drama-filled are characteristics normally reserved for reality television contestants but now they're key points in our idols. That's another subject for another time though. What I'm trying to say is if someone see's you voting with a one-word response they're not going to feel compelled to actually break down their process into explaining why they voted the way they voted. It's stupid but it's true. "He didn't explain his vote why should I?" is a common state of mind. To counter this staff members, such as yours truly, lower voters VP (voting power) until their votes don't matter at all (0VP). In theory the rest of the site would balance the non-essential votes but more and more frequently I'm starting to see battles with 0VP across the board and pretty soon only a few of us are going to have a say in who wins and who doesn't.
TL : DR Explain your votes to receive feedback and proper votes back on your battles.