This is a quote from the book "On Zero Confirmation Transactions" by Chris Pacia
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...t thousands of zero-conf transactions. We don’t need it to be impossible to double-spend, we just need to mitigate the risk sufficiently to where it can still make business sense. An occasiona
l double-spend against us is worth the cost for the improved user experience.
It’s a straw man to suggest we think zero confirmation transactions are “100% safe”. They a
ren’t, but they don’t need to be to serve the purpose.
Given double spend detection, it becomes very difficult to successfully defraud a retail...