The Matter of Work Anniversary Reply
A work anniversary appeared in the notification feed. Congratulations have arrived from people who have not spoken to this person in months. They arrived within fifteen minutes of each other.
The notification appeared at 9:04am.
Within three minutes, the first congratulations message had been sent. By 9:22am, nineteen messages had accumulated in the notification thread.
The messages were of two types:
Type A: Brief acknowledgment. "Congrats!" or "Congratulations!" These are complete as they stand. They require no reply. They were sent because the notification created a social obligation and the shortest fulfillment of that obligation is a brief acknowledgment.
Type B: Extended acknowledgment. "Congrats! Here's to many more!" or "Wow, [N] years! Time flies!" These contain both the acknowledgment and a small contribution to the occasion. They take slightly longer to write and create slightly more of a relationship signal.
The Fifteen-Minute Cluster
Nineteen of the twenty-two congratulations arrived within fifteen minutes of the notification. This is because the notification appeared for all connected people at approximately the same time, and the social impulse to respond is strongest within the first few minutes of awareness.
After the initial cluster, the threshold for responding rises: the person has already received many congratulations, and an additional one adds less. Three people responded after the cluster, probably encountering the notification later in the day.
The N Years Problem
One message said "Can't believe it's been six years!" The anniversary was for five years. The sender noticed this immediately after sending and sent a correction: "Five years! Amazing." The original message remains in the thread.
The anniversary was acknowledged. The year was incorrect. Both facts are now visible in the thread.
The Reply
The person replied to the thread: "Thank you everyone!" This is the correct reply. All twenty-two messages have been acknowledged. The exchange is complete.