Theft-deterrence devices and methods adapted to assist in theft deterrence/prevention of machinery, for example, a man lift, whose controls include a joystick. Such a device includes an enclosure having an interior cavity defined by and between oppositely-disposed first and second ends of the enclosure, and an opening in the second end that communicates with the cavity and sized to enable a joystick to pass therethrough into the cavity. The cavity accommodates at least a portion of the joystick sufficient to prevent operation thereof. The device further includes an arm having a first portion permanently attached to the enclosure, a third portion comprising a through-hole that enables a shackle of a locking device to pass therethrough, and a second portion that permanently joins the first and third portions.