B52T38, the short and dirty answer to your question as to who and why is unemotional Market Makers and people who are purely in this for profit, regardless of who the company is and what their mission is. Remember, emotion plays zero part in their decision making, which is one of the reasons they're successful. I am fairly certain that MOST of the time, they have zero idea regarding the fundamentals of any given company they decide to short. They are primarily looking at technicals for opportunities to short. This is their business, pure and simple. Morality or heart plays no part in their decision-making process. I know I'm painting with broad strokes here and that there may be some who aren't so cold but if there are, they are few and far between and probably either aren't as successful or they aren't in the game for very long.
As to your question about how they can sell shares they haven't borrowed or even own, that's just how the system is set up. There's the right way (legal/legit) and there's the illegal naked short way and that is a HUGE study in of itself. You can read for days on that subject alone. Don't let anyone tell you it's impossible because it's very real and the way it's set up allows those who are supposed to 'protect' us from this type of activity to have plausible deniability. They turn a blind eye and vehemently deny that it happens. There are mountains of evidence to the contrary.
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