I would say that music scan programs work much better now than several years ago. Most of them do a fairly good job when scanning good quality and clean charts, but most of them fail miserabily if you try to use them with old / deteriorated / hand material.

The best software I've found until now is PDF to Music Pro, from Myriad Software. It doesn't perform any OCR process, instead it extracts information directly from the PDF, so if you're using PDF files produced by any notation software (Musescore, Sibelius, etc) as a source material it will work near perfectly, otherwise it won't work AT ALL.
http://www.myriad-online.com/en/products/pdftomusicpro.htm


I've just tried Scanscore, which in fact is a module of the Notation Suite Forte 10 that can be bought separately. It works fairly well and is very easy to use, but again you need to use clean, commercially produced charts.
https://scan-score.com/en/

BIAB 2024, latest build.