I’m assuming they tend to drift towards shores because people find those messages, but I don’t know what percentage of messages are never found because they’re still drifting in the oceans.
They drift randomly what you are thinking of is a specialised form of survivorship bias the ones that randomly make it to shore are the ones that don’t stay in the middle of the ocean or sink to the bottom. https://youtu.be/geOdDSs0tjY
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