... called "answering machines", and when I was young, you didn't have either. Either you reached someone and left a message, or the number rang (never more than six times unless you were an insensitive clod), or returned a busy signal (ask an old). Fancy-pants people had secretaries who took messages on slips and routed them to you at the office. And all of this increased the costs of phone-based annoyances.
Another side of this is that wired landlines are dying, but costs remain.
or you got 'tu-du-doot', in which case you fat-fingered the wrong number 🤣
Generalistic and moderated instance.