Digitising a herbarium is often described as a scanning project. Scanning is the cheap part. A high-resolution image of a pressed specimen, with no structured record behind it, is a photograph of a plant — not a record a researcher can query.
The value sits in the label: collector, date, locality, determination history, and the accession numbers that tie the sheet to everything else in the collection. Much of that is handwritten, in several hands, across a century.
Getting it into a database means transcription, reconciliation against accepted taxonomy, and a decision about what to do when the label disagrees with the current name. Those decisions have to be recorded too, or the next curator inherits an answer with no reasoning attached.