Comment by lukifer

My pet hypothesis: with the vast scale of the universe and the light-speed limitation, when it comes to potential conversational partners, the universe selects in favor of extremely long-lived life-forms (possibly "artificial"). Such life forms would be only be interested in interacting on highly protracted time scales; think "Space Ents". Given also that sending signals into deep space is extremely expensive and energy will always be finite, communication with new worlds is sought only rarely, perhaps one targeted ping per world every 10,000 years, each an attempt to start a dialogue to be carried out laboriously over millions of years.