%%Sorry for the metaphors.
They key concept here is that you are in an auction market. So, let's say you come into the market with a bid for 2000 shares and the bid/ask is 100 shares bid and offered on each side. You have just shown yourself as a motivated buyer who is able to lift the current offer.
Your choice is to keep your limit order and standfast until somebody hits your bid at your price. But, then who is the aggressor in this case? It is you. Basic supply and demand. Your relatively large demand causes the demand/supply curve to go up thus resulting in a higher equilibrium price.
So, do you wait with your bid while everybody dangles higher offers in your face and risk an unfilled order (have the market get away from you) or do you chase the offers higher? Vice versa for selling 2000 shares.
Unlike shopping at a store, there are no quantity discounts. Oops. Is that a metaphor?
Good answer xandman+ that is why many traders/investors prefer liquid, large volume markets.Linker 2k ;you may have gotten a more exact answer with an exact stock symbol; however i would not blame you for keeping it private.
Another advantage for liquid markets, like SPY for example, is the market will bounce around in a bull market or bear + most likely hit your limit order [ in time]- NOT so with illiquid, low volume stuff.Hope this helps; Blair Hull said he was the slowest market maker...... not that he takes 20 days.....LOL