Brake sensor question

Hi Hugh the silver coloured lever is the mechanical brake lever sensor which I had on the other bike now just connected to the bike as a sensor only, a little pull cuts the motor just in case I happen to need it for changing gear etc, most of my riding is done on gravel paths and roads so think should be ok without brake sensors, and there’s no requirement here to have them , l too have ridden all sorts of motorcycles over the years on the roads only I have given them up as now to old lol. Just have to make do with E bikes nowadays not a bad thing as they were getting a bit too dangerous.
If thats the case the answer may be that the small round magnet which was or should have included with the sensor must virtually touch the sensor in order to power the motor.
Where I live brake sensors are required in case of a runaway situation. That could be a stuck throttle (which has happened to me when winter riding in the woods after a wipeout) or possibly some other type of electrical malfunction. They are a safety system and I have met rider's here who don't use them. That goes to personal choice.
I also have owned and ridden many motorcycles and you are right, the throttle is spring loaded and there is always the clutch.
Where I find the brake sensors useful is on my rides down tight singletrack trails. When coming to a turn on the trails I ride if you stop pedaling shortly before a turn there is a short lag before the motor cuts out. Enough so that a couple of my newbie friends stuffed their bikes off the trail and into the bushes. Just lightly touching the brake lever enough to trigger the sensor instantly cuts motor power, you make the turn and resume pedaling. Not an issue on street riding generally of course.
Makes sense, if your motorcycle throttle were to get stuck you have the clutch then kill switch but since you don't have a clutch... I don't have a throttle so one less thing to get stuck on but it would probably be a good idea to have at least one brake sensor set up.

It wouldn't be hard to set up a kill switch with a normally open switch that would be easier to hit that your control power switch, you could just use one of your brake sensor wires.