Revealing mistake: A sign's wooden support gets shot at the beginning, but you can see where the pre-prepared weak point is in the support before it gets "shot."
Continuity mistake: When "Lefty" is at the car crash site, you see a blue mobile home going down the road, but it is not there in the next shot. (You may not be able to see this in the full screen version (4:3)).
Other mistake: Leatherface attacks the Mercedes. The pick up is driving backwards, the Mercedes forwards. The Mercedes should easily be able to outpace the pickup.
Continuity mistake: At the radio station, Leatherface cuts into the tube with the beer cans on ice. In slow motion, the chain comes off the chainsaw. After the cut, the chain is back on.
Revealing mistake: Leatherface attacks the Mercedes. The pick up is driving backwards without the reversing lights coming on. Most likely a reversed shot.
Continuity mistake: The tape recording of the killings Stretch has is in her right hand. A shot later, it's suddenly in her left hand with her purse in her right hand. (00:16:18)
Chosen answer: That's how telephones worked back then. It has to do with the lack of a disconnect signal being sent by the called party, which phone companies have now. Back then when someone called another person, they were paying for the call and thus it was felt that they're entitled not to be hung up on and the line would not be "free" for the person being called, even after they hung up. This also meant if someone was called and they picked up in one room, they could say "hold on I'm going to switch phones", hang up, go to another room and pick up the phone and the caller would still be there. It was also a great way to scam or annoy people by calling them and not hanging up. Some countries still maintain this method of operation, largely because some people have become used to it, although nowadays it's by choice, not by technical limitation, and the length of time the line is held open is significantly reduced.
Bishop73
Yeah that's actually true. in the 80s we used to call up talk radio shows from isolated, seldom-used phone booths and then leave the phone off the hook. No more calls for hours until they straightened it out with the phone company. we called it 'jock blocking'.
That's not true my brother would prank call KDKA in Pittsburgh constantly they had no trouble hanging up. If people called our house there was no trouble hanging up.
That's exactly how it worked if the line didn't have a disconnect signal.
Bishop73