Hindmost, to short a stock you must must first borrow it then...

Hindmost, to short a stock you must must first borrow it then onsell it. You end up paying a stock borrow costs and any dividends the stock pays. It can get pretty expensive pretty quick. Not every stock falls like qbe.

The reason the reduced buyer count argument isnt correct is because the shorter is a guaranteed buyer sometime in the future and he pays the borrow costs plus dividends for getting this privilege of delaying of buying stock back.

Also, the thinking that derivatives market should be used to short is misinformed. When you use derivatives what do think the counterparty does? They take commission from you to place a synthetic short on the market.