Per Autodesk knowledge center: There are about a baker's dozen steps to convert a single Revit schedule to spreadsheet format.
Note: Revit 2022 and newer can export straight to CSV format, thus significantly cutting the processing time. Additionally, before Revit 2022, users could utilize Dynamo, DB Link, or other FREE add-ins, which is also a tremendous time-saver. However, often these alternative options do not include the intelligent element identifiers that allow for interconnectivity.
An example within an Autodesk Revit sample project, utilizing the traditional (as described above) data export and producing 3 PDFs required about 2:35 to complete both tasks and share via email. Refer to this un-abridged video.