The problem is people being satisfied with a free application for doing mission critical calculations. Yes, you buy an MS Office licence and Excel comes free. That is fine for run of the mill everyday calculations, but it is not OK for mission critical work and it is NOT ok for the CFO or anyone who advises the CFO on his decisions. Those important financial people should use a spreadsheet like this http://www.resolversystems.com/products/resolver-one/ backed up by a team of software developers who write unit tests for the spreadsheets and validate the calculations.
TLDR is that the ResolverONE spreadsheet writes Python code as you manipulate the spreadsheet. A software developer can then organize that Python code, write unit tests for the code and validate that the calculations do what the CFO intended. Once this extra work is done, then the business can have confidence in the results of the calculations. But the user interface, i.e. the spreadsheet that end users see, is the same as it was originally.
This allows mission critical software development discipline to be applied to the development of spreadsheets. I suspect that the existence of a tool like ResolverONE is one of the factors that led the SEC in the USA to require Python source code for new derivatives that are created, so that there is a standard way to express the calculations of the derivative.
TLDR is that the ResolverONE spreadsheet writes Python code as you manipulate the spreadsheet. A software developer can then organize that Python code, write unit tests for the code and validate that the calculations do what the CFO intended. Once this extra work is done, then the business can have confidence in the results of the calculations. But the user interface, i.e. the spreadsheet that end users see, is the same as it was originally.
This allows mission critical software development discipline to be applied to the development of spreadsheets. I suspect that the existence of a tool like ResolverONE is one of the factors that led the SEC in the USA to require Python source code for new derivatives that are created, so that there is a standard way to express the calculations of the derivative.