This answer, by its own admission, does not answer the question. Other users have pointed this out as well. Indeed, the answerer admits:
Fair point that I should have been more on point to the OP's question. I think that trying to decide why a hand count is "better" is the wrong question. To me the more pertinent question is... [emphasis added]
I flagged it under the following category:
This was posted as an answer, but it does not attempt to answer the question. It should possibly be an edit, a comment, another question, or deleted altogether.
with the following reason:
This does not answer the question: Why is “hand recount” better than “computer rescan”?
But my flag was declined. The baffling reason given was the following:
declined - flags should not be used to indicate technical inaccuracies, or an altogether wrong answer
Why was the flag declined? Why was this reason given for declining the flag?
Edit: Note that the body of the question is as follows:
My initial judgement is that a "computer rescan" would have less chance of being biased and less change of making mistakes than a "hand recount", and so the "hand recount" can only introduce more uncertainty and a worse quality result. Is there any reason I should think otherwise? And if the result is not qualitatively better, then what? 2 out of 3?
In other words, the question is specifically asking about these aspects (bias, reliability, security, certainty, quality, etc.).