> The upside of Excel is that the feedback is immediate so you have a chance of spotting the error if you're expecting a certain output.
Only some errors are obvious just from a glance at the result set. For other errors, Excel makes the developer's job much harder. Subtle bugs can hide the code of an individual cell among thousands, and the user has no means of clearly abstracting that code out.
I completely agree. There are some things you can do in Excel that are nearly impossible to track down. There are auditing tools that help, but you can truly ruin a spreadsheet in undetectable ways if you want (or more likely, don't want).
Only some errors are obvious just from a glance at the result set. For other errors, Excel makes the developer's job much harder. Subtle bugs can hide the code of an individual cell among thousands, and the user has no means of clearly abstracting that code out.