I used to work in the financial industry where lots of things are built in excel, and I have my fair share of VBA programming. What I can tell you is:
1. VBA is aweful. Sure it can communicate well with the spreadsheet, but the language is quite bad, and so is the IDE. You can't write anything complicated.
2. Excel is really good if you want to do some calculations, and it allows you to build something user interface-like really quickly.
So building some models in Excel works fine as long as whatever you want to do is contained in the built-in functions or is not too complicated to be made in VBA, but passed a certain point in complexity, you really want to use another language. Banks have some addins in C++ or C# to export their own functions to excel, and really being able to call a more flexible language like Clojure can simplify life.
What would be really great is the equivalent of the VBA editor for C# and VB.net (there is already one for F#). With roslyn now open source I hope it will dignificantly lower the bar for someone to create it.
In fact Microsoft did create it (VSTA) but then killed it before it could make its way to office. I have no idea of why they think users are better off with VBA, a language that hasn't been updated in 15 years.
1. VBA is aweful. Sure it can communicate well with the spreadsheet, but the language is quite bad, and so is the IDE. You can't write anything complicated. 2. Excel is really good if you want to do some calculations, and it allows you to build something user interface-like really quickly.
So building some models in Excel works fine as long as whatever you want to do is contained in the built-in functions or is not too complicated to be made in VBA, but passed a certain point in complexity, you really want to use another language. Banks have some addins in C++ or C# to export their own functions to excel, and really being able to call a more flexible language like Clojure can simplify life.