I guess there are various reasons to short a stock. The obvious one is when you expect super bad news that would drop the stock big time. Say Sun Edison for example, it went from 30$ per share to nothing and went BK. On the other hand, the constant shorting on a news pop and covering lower is a legit way to keep a stock pin down. I doubt anyone is seriously interested in doing this.
I think it's a trading strategy. For example, you go long at 1.6 and then sold at news pop over 3, then immediately short it. The profit taking + shorting drops it down again. You then cover at say 2.5 and go long again. Repeat when it pops over 3 again. This strategy has been used by a lot of professional traders. You need a broker that's willing to lend you shares to short the stock, so it's not something everyone can pull off. You're basically earning double on both up and down of the stock. Shorting has huge risk where there are no ceilings. But, if you got warrants, that's like insurance if say you got unlucky and a short squeeze happened. You can safely cover and not lose a Penney.
Now, this isn't a bad thing for the stock in the long run. So when company fundamentals develops higher value for the stock, it gets priced in and move higher eventually.