My friend had a small magnet and he warned me not to use it to pull things towards it too often as that would exhaust its magnetic powers.
Can a magnet become demagnetized by overuse?
In materials like iron, the atoms themselves are little magnets. In the natural or neutral state, these atoms all point in different directions. In a magnet, the atoms all point in the same direction.
To de-magnetise a magnet, the alignment of the atoms needs to be disturbed in such a way that they are pointing randomly in different direction, as in the neutral metal. This can be done in either of three ways:
(a) by heating the magnet over a gas flame.
(b) by hammering it for a few minutes, or
(c) by dropping the magnet from a height of over 100 ft.
The magnet cannot lose its magnetic properties due to over use.
Picture Credit : Google