Orders for 5000 get filled many times over the course of a typical trading day. But only an idiot would show 5000 - they Iceberg the order.
I have wondered...What is the disadvantage of just planting a 5,000 lot order at a price point, for all to see? If anyone wants to go past that person's price point, they will have to dig through it. That person "owns" that price, and anyone who wants to pass through it will have to deal with them.
Not sure what you mean but say a sell order for 10,000 shows up in a stock that normally doesn’t have that size offer. Buyers will back off and not dig through. Unless just a large enough institution that wants it “now” regardless of price. Same with a buyer showing wanting to buy 10,000 shares sellers will back off.