The build team was very proud when they announced that the application would finally start being built from the source code in version control.
Stuff happens!
Getting on for a decade ago now I was working at Red Gate when they bought .NET Reflector - a decompiler for .NET code - from Lutz Roeder. After the acquisition we started asking people what they were using it for.
Turns out a significant minority of them were trying to recover lost source code, or source code they never had in the first place (e.g., where a supplier went out of business). I don't remember the exact figure but it might even have run into low double-digit percentages. Bear in mind this is a tool that was being downloaded tens of thousands of times every month by all manner of people working for all kinds of organisations of every size and you can see the scale of the problem.
There were a couple of Reflector add-ins that would allow you to take a .NET binary and generate a C# or VB.NET Visual Studio project with all source code from it. The source code was never perfect and wouldn't likely compile first time, but it was certainly better than starting from scratch. Not surprisingly these add-ins were among the most popular.
Granted, times have changed, and I think source control is probably the default for almost everyone these days - although I would have expected that even in 2008 - but, bottom line: I think this sort of thing happens a lot, for one reason or another.
There is no way I could rely on something like that.
Am I the only one that thinks relying on something that has no source code is just asking for trouble and headaches in the future?
But those DLLs aren't the only, or the biggest, problems with the systems. Hence finding the source and building them from it isn't necessarily the top priority, although we are progressively doing exactly this.
How would you go an entire decade without noticing this?
Wouldn't you have to use that missing source code for something within ten years?