Omitting an object has two fundamentally distinct effects. The speaker may present the verb without regard to any particular object, treating it like an intransitive verb. In that use no definite hidden object is meant.
Alternatively, the action may concern a particular object that is unspoken but recoverable through context. The noun is suppressed, but its specific referent is still intended.
The distinction is between “no particular object in view” and “a particular object intentionally unexpressed.” The absence of an accusative noun alone cannot decide which interpretation is required.