When I was a child of around 7 or 8, the topic of chronic thumb sucking came up, as I remember having to do with one of my cousins. I asked my parents if I sucked my thumb. They said yes, but only briefly. “How did you stop it?” I asked. My father said “go ahead and suck your thumb”. So I put my thumb in my mouth and just then my father gently pulled my arm down and my thumb with it out of my mouth. He said “again”, so I put my thumb back in my mouth and once again he pulled my arm away from my mouth. After the third or fourth time I was done and to even a younger mind, I gave up long before I even had a memory of it.
There’s some kind of reverse muscle memory thing going on when your arms (in particular) are restrained. Those arms are how you engage the world and when that access is taken away so is a whole bunch of your power. In the realm of human sexuality, the arms embrace, hold, touch…are touched and become part of the means of how we “transact” our sexual motivations.
For some men, those motivations unfortunately can include unwanted actions of groping, fondling, pinching, ass swatting…you get the point. So to restrain the arms in erotic play, you are taking away a tangible part of a man’s power and requiring him to physically surrender to you and the circumstance that you control. It lets him know in no uncertain terms that you are in charge. Next comes his mental and emotional surrender to you.