Why spreadsheets don't work
Spreadsheets totally fail to separate presentation from content - which tends to mean that the two get tangled together into an unholy mess. That makes it hard to comprehend the model contained in the spreadsheet. And that makes the spreadsheet hard to change.
I can see this at the client I'm working with at the moment, where spreadsheets are used for progress tracking. Different aspects of the project need tracking more closely at different times or under different circumstances, and changing the tracking model used by the spreadsheet is a pain.
Data visualisation is a powerful tool, and spreadsheet graphs and tables can look great, but I want a better tool. One that is still easy to use, but which separates data collection, relationship modelling, and data presentation. Any ideas?