There were states who used automated machines, and tweeked match parameters to allow more through. There are states where courts said they couldn’t match signatures, and where they hired more people without much training, who wouldn’t know how to match signatures.
But Georgia seems to have done it pretty much right. We don’t want to reject valid votes because people scrawl their signatures, or accept votes that are fraudulent.
Signature recognition is a big issue. That’s why liberal activist lawyers filed lawsuits to ban signature matching in Pennsylvania and other places.