Yep.  At risk of adding a &quot;this&quot; comment I&#x27;ve spent years reading on the subject, talking to some of our customers who are HFT, and generally just thinking and learning about it.<p>I still can&#x27;t figured out a single value-add they bring to the table, much less to justify their insane compensation or the incredible technology budgets they carry.  It&#x27;s simply sad to me to see some of these brilliant minds (at least on the tech side where I interact) essentially engaged in ripping off fellow citizens at worst and rent-seeking at best.<p>Of course if you engage them, they will get all hand-wavy about &quot;liquidity&quot; - but I think it&#x27;s striking that not a single person I&#x27;ve talked to has been able to distill the benefit they bring to society in a simple sentence or paragraph.  It always ends with the &quot;most people can&#x27;t understand&quot; which as I get older I&#x27;ve learned is a euphemism for either &quot;I don&#x27;t know&quot; or &quot;I don&#x27;t want to tell you the truth&quot;.<p>Either way, so many billions of dollars taken from the economy and put into useless activity.  Absolutely no one will be able to convince me we need millisecond-level liquidity for markets to function efficiently.