I think this little snapshot of history is quite telling.
How Do Post Office Machines Read Addresses?‘
Not until Christmas of 1997 did the USPS and the University of Buffalo’s Center for Excellence in Document Analysis and Recognition (CEDAR) deploy its first handwritten address-reading prototype, which rejected 85 percent of envelopes and correctly identified the address in only 10 percent of those it read with a 2 percent error rate.
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Today, the large majority of letters sent through the post office are read and sorted entirely by computer. According to Srihari, current reading success rates are above 90 percent… the first human eyes to examine the envelope are those of the postal carrier approaching your mailbox.