Depends on what it is, for anything that uses a web interface or runs as a native app I'd question many years without updates just because the deployment targets shift so much. Most of the apps I really enjoy on the Mac, for example, at least get yearly updates to whatever new MacOS API changes occurred in the major release.

A video game emulator getting an update every decade though? Some low level tool that's never changed since the beginning of time? Yeah, they're done, what's the problem.