Use Full PDF text extraction when accuracy matters, not Fast. Fast mode pulls embedded PDF text and skips the scan pass, so anything rendered as an image - footer addresses, stamps, letterheads - silently drops out of the result. Fast is fine for born-digital PDFs where you want speed; for scans or mixed documents, pay for Full or you will chase missing fields that were never extracted.

Context: Klippa OCR integration docs (Automation Anywhere bot readme): PDF text extraction has two modes - Fast tries to extract embedded text from the PDF for speed, Full scans the whole document. Fast can miss details that live in images, e.g. a company address in a document footer.