Although computer memory is no longer expensive, there's always a finite size buffer somewhere. When a big piece of news arrives, everybody sends a message to everybody else, and the buffer fills.
虽然计算机内存不再昂贵，但总有一个有限大小的缓冲区。当一条重要消息到达时，每个人都向其他每个人发送一条消息，缓冲区就会被填满。