The problem was that, while the Patriot system worked, at first, no one had ever left it on 24/7. It wasn't until they started missing, every launch, that it was discovered that there was a tracking error in the software/radar interface clock, and this resulted in up to a 90 degree launch fault.
A SCUD hit a US barracks at Dharhan, killing 27 troops, and others were hitting Israel, that was supposed to be protected by Patriot batteries.
This prompted Israel to develop their own system...
It's presumed that this error has been fixed.
“Was wondering this as well. Didn’t we knock down SCUDs in the Gulf War?”
They hit some of the Scuds with Patriots, but not all. I was there, and saw the Scuds flying overhead and landing with a boom that resounded for many miles. I also remember the cheering of the West Bank Arabs around us. If I recall correctly, one Scud hit an Israeli underground bomb bunker in Tel Aviv, killing upwards of 100 people.
Yeah it’s long since been fixed.
The newest Patriot (PAC-3) uses a smaller, faster, and more accurate missile. The original system had 4 ready to fire missiles per launcher, with the PAC-3 it’s 16 per launcher.