> The boss says to build a thing, you build the thing. Sounds like a typical entry-level job to me. > They're not making the world a better place; they're not

> The boss says to build a thing, you build the thing. Sounds like a typical entry-level job to me. > They're not making the world a better place; they're not providing a valuable service; they're just exploiting and extracting and skimming some dollars out of the market. Firms providing useful services through their trading allow our economies to prioritize resources more efficiently. Better resource prioritization increases prosperity, which makes the world a better place in a multitude of ways. The useful services provided (for example, increased market stability) go beyond the seemingly-simple benefits of "increased liquidity" and "tighter bid/ask spreads" that are often mentioned. This becomes easier to appreciate once you delve into the enormous number and diversity of traded instruments and their interrelationships. It's far more than just cash equities. Firms pursing parasitic trading are harmful to markets. Their behavior tends to backfire in the long run due to a combination of regulatory action and natural market dynamics. Characterizing all (or even most) HFT firms as harmful is inaccurate in my experience.