Some dictionaries source attestation and try to go for the earliest quotes they can find. How do they find them? Without electronic indexing this must have been impossibly difficult.

The reason I'm asking is that many answers on Stackexchange often conclude earliest attestation and imply earliest use, instead of the logical used at the latest in ... That's a slightly different issue to frame the question, not to make it too broad. To be fair, no inference is made because of this in many cases.

Some dictionaries source attestation and try to go for the earliest quotes they can find. How do they find them? Without electronic indexing this must have been impossibly difficult.

The reason I'm asking is that many answers on Stack Exchange often conclude earliest attestation and imply earliest use, instead of the logical used at the latest in ... That's a slightly different issue to frame the question, not to make it too broad. To be fair, no inference is made because of this in many cases.