Most answering machines are hardwired to pick up after four rings. This design decision is evil.
It is evil because it has the unintentional consequence that whenever the phone rings, and you are home, you must scramble to pick up the receiver before it does. Before answering machines, humans, and not technology, controlled the pace of life in their homes. You could finish whatever you were doing --- complete the sentence you were typing, or politely excuse yourself from a conversation, or rinse the toothpaste from your mouth --- and then walk to the phone in a leisurely and dignified manner. With answering machines, when the phone rings, one must immediately drop everything and dash madly to receive the call before the fourth ring ends (usually about twenty seconds). Humans have surrendered to technology.
(Yes, you can let the answering machine pick up, and return the call later; but in fact this merely forces the problem onto the other party. Eventually, somebody must race their answering machine to pick up the phone.)
This is madness. Answering machines should have a toggle of some kind that controls how many times the phone rings. The elderly, or the handicapped, or people who live in larger residences, or people who just value their dignity, should be able to set the ring count higher to allow more time to get to the receiver. But selectable ring counts are a feature found only on the most high-end answering machines.
And don't even get me started on cell phones. The sophistication of the software and hardware dispersed throughout cell phone system is astounding --- my cell phone alone could probably have run the Apollo moon mission --- but I can't do something as bone-headedly simple as telling my voice mail to pick up after six rings instead of four.