Poor Excel conversion is usually caused by broken or incomplete grid lines:

• When they are incomplete or broken in the image, then the software does not know what to do with those fragments.
• If they are not present at all or solid and intact,  then the conversion works well.

To solve poor Excel conversion:

• Use the Adjust image tool to either darken the lines or eliminate them completely.
• If necessary, rezone the spreadsheet as a table using the Table tool in the Zones tab.
  It may be necessary to delete all the zones by clicking the Delete all zones button and starting fresh.
• Set the output to XLSX (Excel). Then click the down arrow beneath XLSX and select Spreadsheet settings. Now set the Layout option to Create body text.
• Go to the SpreadsheetML options tab and check Convert figures into numbers to display number as number and not text.