The starting numbers are a modelled example. They are not a measurement, and they are not drawn from any survey of what review actually costs, because there is no such source behind this page. Replace all four with your own.
The right hand column is the price of the software. It is not a claim that a case takes no time: a case still has to be scoped, the flags still have to be worked and the bundle still has to be released. Compare a price against a price, and put whatever review time remains back into the left hand column.
The right hand column prices pages of generated output rather than pages of the file you upload, and every document counts as at least two pages, which is why the two page counts differ on a case of short documents. The cap a spreadsheet's pages are counted under is not modelled here, because this page does not know which of your files are spreadsheets.
Prices exclude VAT, which is added to your invoice where it is due, and a monthly subscription is a month rather than a case.