Lots of reasons. There's reasons to show and hide your hand. But there's nothing inherently wrong with announcing your intentions to buy or sell at a given price.why would anyone other than market makers want to publicly announce their pending orders by putting it on the order book
Most of these orders go to the pit or are traded during open/close auctions. If you watch the depth enough, you'll see out-of-spread prints for large orders. These are typically institutional orders with a reporting lag.if i were a big institutional trader i would use iceberg to hide my big orders from BOTs and other traders, they won't show in the market depth but they'll be visible when executed, if i wanted to get more stealthy i would spread those orders across multiple prices, nobody would see a damn thing.
And just a general thought on automation / bots / algos / etc... Why does everyone hate this? The tape is nothing more than a representation of the behaviors of people in aggregate. That something was programmed previously does not mean that it doesn't reflect human behavior. The only difference is, the algo decision making process as already been completed (which means this can in fact be predicted, unlike nearly everything else market related), so you're not up against human emotion. So to my mind, you're up against a trader who is perfectly cold and rational, will pervasively adhere to their pattern, and isn't changing their mind based on emerging information. How does that enhance the readability of the market?
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