Just imagine 50 different poker tables in a casino. Only 50 dealers see everyone's card and the 7 billion people playing poker only knows its own cards.
L2 is a good tool, but more often than not it is deceptive. Can you imagine if I had 100 orders on ABCD stock but you only see the one (1) order as an inside quote. I know what the other 99 are doing. You don't.
At the end of the day, I go the Ulysses pub on Stone Street where quite often traders party up after hours, and I get to know what the seller is doing.
You don't, nor does L2.
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