[JonChesterfield]

Defining substantial as written by a team over a long period of time seems to be putting the value in the wrong place. Is the important thing what the software does, or that it took a lot of people a long time to write it?

[magicalhippo]

I didn't say long time to write it. I said maintained by a team over time.

Sure there might be some substantial software that was written as a one-off (ie not modified after release), but that's the minority by far.