If it lingered in the public consciousness, it was because of its durability, not repeated reminders. Content had finite endings and deaths, not asymptotic approaches and long-term vegetative states from which resuscitation is always an option.

Consumers had to make similar bargains: If you went out on a Thursday night during the 1990s, you missed NBC’s “Must See TV” schedule (unless you taped it) and understood that it would be a while before you could see it again. (It helped, too, that there was less media competition in previous decades and, in the case of TV, that dramatic series were generally less complex, so that missing an episode of “Dynasty” might not set you back as far as skipping one of “Breaking Bad.”)

Now, with just about every airing of a much greater number of shows obtainable at any moment, there is no excuse for missing one — and, therefore, a more urgent compulsion to catch up, in case you missed it.

Today, both the outlets and the individuals who are responsible for the work are aware that they have a limited window in which their content can go viral and outlive its short stay on a home page. When it fails to do so, as, by definition, almost everything must, it may seem to them like a disheartening screen-age Zen koan: If an article about deforestation is published but no one clicks on it, did it actually exist?

Hence ICYMI. In an earlier time, the full verbal formulation meant that the recipient was supposed to see something of a certain degree of importance (a note, an email), and the sender was gently reminding you of its oversight.

Now, the very shortening of the phrase is a byproduct and acknowledgment of the velocity of information against which its attached link is racing. The implication is that you probably have not seen it, and it’s not necessary to your existence, but the sender would like to bring it to your attention anyway, please. It serves as a call of desperation as much as an announcement: Can you hear my whisper in these howling winds? In fact, ICYMI is often used as the second or third attempt to link to something (which suggests the content is not taking off organically) as a means of excusing the repetitive promotion.