Similarly, I think there are only three versions of software.
Version 1 is what you write fast, to ship it quickly. Corners are cut. It isn't even held together by duct tape and baling wire. It is glued together with bird spit. But it gets the crucial first dollar of revenue. Version 1 is programmed by hackers.
Version 2 is what you write more slowly, painstakingly, to replace version 1 before its innards inevitably spill out onto the pavement. Version 2 is paid for by version 1, but is programmed by the math-poets, the software "engineers". It is very elegant and clean, but doesn't always do what the customer needs. There is zero technical debt. People weep when reading the code, it is so beautiful. But it still doesn't export the management report to Excel yet.
Version 3 is what you get after version 2 has been in production so long that many of the conscious design decisions introduced by forward-thinking architects have been patched out and replaced with simpler things that just work, and are easy to maintain. The ultimate goal of version 3 is to replace itself with a shell script, and then take a nap until a new requirement or feature request comes in. It does everything the business wants, but everything is a massive wad of cruft, and there are legacy bits that no one wants to touch.
The number reported by the software has nothing to do with this. A lot of software never gets out of version 1, or goes straight from 1 to 3, or skips 1 and starts at 2.