Most of the practical difference between a capture implementation that works and one that irritates comes down to a single configurable number: the confidence level at which an extracted field goes straight through rather than to a person. It is genuinely a trade-off, it should be set from evidence rather than left at a default, and almost nobody revisits it after the first month.
What the threshold trades off
Set it high and more fields go to review, which costs time but catches errors. Set it low and fewer fields are reviewed, which saves time and lets some wrong values through to the ledger. There is no universally right answer because it depends on your document quality, your volumes and what a wrong value costs you downstream.
How to set it from your own evidence
Start strict for a month and record, for every field a person corrected, what the software's confidence had been. That gives you the distribution you need: if almost nothing below a certain level was wrong, the threshold can come down. This is an hour of analysis that pays for itself repeatedly, and it is specific to your documents.
Revisit it when the input changes
A new large supplier with an unfamiliar layout, a change of scanning equipment, or a shift from post to emailed PDFs all move the distribution. The threshold set a year ago against different inputs is no longer the one your evidence supports, and a quarterly glance at the correction rate is enough to notice.
Questions people ask about ocr for accounts payable
Should the threshold differ by field?
Ideally yes. Totals and dates behave differently from line descriptions, and a single global threshold over-reviews the easy fields and under-reviews the hard ones.
What if the software does not expose confidence?
That is a meaningful limitation. Without it you cannot target review, and you are choosing between checking everything and checking nothing.
Does a correction improve future accuracy?
Often, particularly per supplier. Ask what a correction actually changes and how long before the effect is visible.