Some magic items come with a set number of charges. The number may be fixed or determined by a dice roll listed in the item's description. These are not daily uses unless the item states so. Charges do not regenerate on their own. Once an item's final charge is used, its magic is spent and the item becomes non-magical.
In rare cases, an item may retain a faint magical resonance. The DN may allow it to be recharged under special circumstances - the right ritual, a costly payment, or by seeking an individual or creature capable of re-infusing the item with new energy. Such methods are never assumed and always require DN discretion.