I think it means that this was the first conflict that it had in against Scuds. There was a software update made a few days before this incident that was in response to another Patriot/Scud engagement. The big issue with this time was that the missile didn't even fire.

http://embeddedgurus.com/barr-code/2014/03/lethal-software-d...

It's interesting that there were 6 software updates to the Patriot missile batteries during Desert Storm, several of them were specifically to fix the clock errors.

It would be interesting to see the data for the misses and the hits compared to how long each system had been online for and what version of the software it was using.

Today's patriots are better (PAC-3, PAC-4 in testing) but still have several issues. I remember reading somewhere where a pilot got so mad that he was constantly being locked on by friendly Patriot batteries that he shot a missile at a friendly battery. http://books.google.com/books?id=7cU8Kpzu9osC&pg=PA339&lpg=P...

These seem to be mostly RADAR issues, I can't imagine how difficult it would be to program a missile to intercept another missile, there's hundreds of variables involved. I'd be willing to bet that these days they can run them through a computer simulator and detect most of these issues.

Unrelated to the missile but relating to the original topic: http://www.wired.com/2012/11/google-spanner-time/