[traK6Dcm]

> I understand they are not making the world a better place, but are they making it worse?

Most people would argue that they are not directly making the world a worse place, but rather that they are sucking in talent that could have used their skills in other places to make the world a better place. For example, many talented Physicists ended up in trading companies a few decades ago. Today, you can make a similar argument for companies such as Google or FB who probably have tons of extremely intelligent scientists working on ads.

> Something that I have heard is that they are providing a service by providing liquidity to the market.

It's unquestionable that they provide liquidity, at least most of the time. That's good. What's questionable is whether they are doing it in an efficient way. Their primary goal is not to provide liquidity - it's to make money. Liquidity is just kind of a side effect of their activities, which is an elaborate race to "beat" other firms through speed and algorithms. Most of the resources go towards that, but don't result in additional liquidity, most of which is probably not even needed. It's like saying "FB provides an important service by allowing you to message your friends" - sure, that's not wrong, but that's not their primary goal. And you don't need a trillion dollar to make a messaging app. The difference is that FB also does lots of other things, so it's unclear how much of their resources are actually wasted vs. potentially used for "making the world a better place" - it's not quite as obvious that they are wasting a lot of talent and capital.

The other question is what the alternative would be. Markets run by human traders were significantly more unfair than anything we have now, but HFT was never meant to happen, it was just result of markets becoming electronic and transparent, and people trying to extract more money.