Degaussing isn't effective on modern drives because they are too well-shielded.
From the usatoday.com
Degaussing is the process of decreasing or eliminating an unwanted magnetic field.
From the en.wikipedia.org
There are some domains whose magnetic alignment is not randomized after degaussing.
From the en.wikipedia.org
Normally, assured destruction means degaussing magnetic media or shredding optical disks.
From the economist.com
This degaussing field is strong enough to remove shadow mask magnetization in most cases.
From the en.wikipedia.org
The residual magnetization of the core can be removed by degaussing.
From the en.wikipedia.org
Until recently, the most common use of degaussing was in CRT-based TV sets and computer monitors.
From the en.wikipedia.org
Proper degaussing will ensure there is insufficient magnetic remanence to reconstruct the data.
From the en.wikipedia.org
A degausser is a device that can generate a magnetic field for degaussing magnetic storage media.
From the en.wikipedia.org
More examples
Demagnetize: make nonmagnetic; take away the magnetic properties (of); "demagnetize the iron shavings"; "they degaussed the ship"
(degaussing) the process of making a (steel) ship's hull nonmagnetic by producing an opposing magnetic field
Degaussing is the process of decreasing or eliminating an unwanted magnetic field. It is named after Carl Friedrich Gauss, an early researcher in the field of magnetism. ...
To reduce or eliminate a magnetic field, especially from the hull of a ship, or from a computer monitor
(Degaussing) Magnetic stripe data erasure.
(Degaussing (of monitor)) An operation that is activated by pressing the DEGAUSS button on a high-resolution color monitor. Residual magnetism and charge are removed by this operation so that the electron beam can land on the proper phosphor and render correct colors.
(Degaussing) A process of destroying computerized data by leaving the domains in random patterns with no preference to orientation, which then renders previous data unrecoverable. ...
(Degaussing) The process of demagnetizing (removing the magnetic field) of a monitor that can build up over time or occur from external sources, to remove the color or picture distortion caused by the field.
(Degaussing) This function removes magnetism from the CRT, on some models this is activated automatically once the power is switched on. Most models include this function within the user OSD menu.