Economy is useful when the deleted object has already been identified or can be inferred so easily that repeating it adds little. The utterance then directs attention toward the new part of the report.
«سَأَلْتُهُ فَأَجَابَ»
I asked him, and he replied.
Here, “he replied” need not restate “to my question” when the relation is obvious. If the main issue were which of several questions he answered, an overt complement could instead be needed.
The suitability of economical omission depends on the audience's shared information, not on the verb form alone.