But it brings back bad memories of the stock market crash of 1987 when some Nasdaq dealers simply wouldn’t pick up their phones. They knew the investors on the other end were looking to sell their stocks and as market makers, these dealers would be obliged to buy—and they didn’t want to buy! In the aftermath of that incident, enraged investors demanded that the SEC prevent it from happening again. The Commission responded by forcing changes on Nasdaq, including mandating that market makers respond to messages on the fully electronic Small Order Execution System.
Today, the fully-automated Nasdaq market, with its market makers often using HFT techniques, is the very model of an efficient market that has dramatically lowered costs for investors.
Contrast that with the findings of the joint government staff report on the US Treasury “flash rally” which found high frequency traders “as a group continued to provide the majority of order book depth and a tight spread between bid and ask prices throughout the day, even during the event window.” In short, HFT answered the call.