Check Skip Blank Pages Before It Removes a Faint Original
A scanner can feed every sheet and still omit an image from the saved file. Blank-page detection is one possible reason, especially when a page contains only a faint note, small page number or light stamp.
Count the sides that matter
Before scanning, work out how many sides contain information. For a duplex bundle, the number of sheets is not the same as the expected number of saved pages. Note intentionally blank sides separately rather than assuming a shorter PDF is correct.
Find the scan profile's Skip Blank Pages setting, if available. Epson's Scan 2 Linux manual explicitly warns that some pages can be incorrectly skipped, and that a high detection level can classify lightly coloured originals as blank. The same controls are not present in every scanner, operating system or scan mode.
Make a short trial containing a normal text page, a genuinely blank side and the faintest meaningful page. Save the result and check each expected item. A progress counter showing that sheets passed through is not a substitute for inspecting the file.
Separate detection from feeding
If the faint page is missing, rescan the trial with blank-page skipping disabled where supported. If it now appears, the comparison gives you evidence to adjust or avoid the detection feature for this document type.
If the page still does not appear, investigate page selection, saving and the feed itself rather than continuing to change blank detection. Keep the original order intact so you can determine exactly what was omitted.
For a mixed bundle, it may be simpler to retain blank pages during capture and review them deliberately afterwards. Do not delete a page merely because its thumbnail looks empty; zoom in before deciding that it contains no information.
Once the batch is saved, reconcile its page count with your preparation notes and check sequence. Keep the paper until that review is complete. The useful automation is the one that removes verified blanks without removing content you needed to retain.
Sources: Epson Scan 2 blank-page detection.