One major reason why another Terminator movie probably won't happen: simple Hollywood economics. Though Terminator 3 under-performed, grossing less than predecessor Terminator 2, Salvation, and now Genisys, were out-and-out commercial failures. And that, in Hollywood, is the ultimate no-no. A Hollywood blockbuster can offend its audience, have critics to declare it the worst film ever made and cause viewers to leave in droves before the halfway point - but as long as those people went to the cinema in the first place and paid for their tickets, then there's absolutely no problem, and you should probably expect a sequel. If a blockbuster fails to break the bank, however, then that's a different story altogether; when a film fails to make the cash it was expected to make, in Hollywood that's called an outright disaster. The Terminator franchise has two strikes already - whether studios will take a punt and risk strike three is uncertain, but the numbers for Genisys (on track to becoming the lowest-grossing Terminator sequel) definitely don't look good.