The Terminator Why doesnt Skynet just send more Terminators back

You d think Skynet would want to make sure the job was done. But no, it just very occasionally sends one solitary Terminator back in time and then assumes it s done completed its mission a slightly risky strategy for a supposedly infallible sentient machine one might think. It s not as if there s a shortage of Terminators lying around. However, my favourite answer to this was suggested by critic Devin Faraci, and neatly ties in Terminator Salvation into the franchise in a way that makes it suck a hell of a lot less. Skynet is damaged at the end of Salvation, almost beaten in fact. It s been driven to extreme action using the last of its power to send one Terminator back in time in a desperate attempt to destroy the future, and thwart its own destruction. I really wish they d put this on screen.