Here's why:
* It's a compound tense: The passé composé is formed by combining the auxiliary verb "avoir" or "être" with the past participle of the main verb. This "compound" structure is what gives it its name.
* It describes a completed action: While the passé composé can be used to describe actions in the past, it focuses on the completion of the action rather than the ongoing process.
In contrast to the English "perfect tense", which is more concerned with the state of completion relative to a specific point in time, the passé composé focuses more on the simple completion of an action in the past.
Therefore, while both tenses indicate completion, the French "passé composé" focuses on the fact of completion itself, while the English "perfect tense" often emphasizes the state of completion at a specific point in time.