meetup-rsvp-leaky-abstraction.md

meetup-rsvp-leaky-abstraction.md

When “RSVP Today” Stops Making Sense

I received this Meetup email today and could not make sense of it.

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My name did not appear among the truncated list shown under 13 waiting.

Hypothesis: The event page exposes an internal bookkeeping contradiction directly to users. It can simultaneously show a waitlist (proof that demand exceeds capacity) and a message saying the event is “2 RSVPs away from 5 RSVPs” (implying insufficient interest). From a user’s point of view, these two states cannot both be true. The confusion arises because the system treats “minimum RSVPs” and “attendance capacity” as independent counters and surfaces both without resolving their meaning. The result is a leaky abstraction that forces users to reverse-engineer organizer mechanics instead of clearly answering the only question that matters: what is my status, and what will happen if I click RSVP?

I saw this.

“You are 2 RSVPs away from 5 RSVPs.”

Immediately below it: a large RSVP today button.

Elsewhere on the page, I could also see that the event had a waitlist.

At that point, a basic question became impossible to answer:

Is this event short on interest — or oversubscribed?

Why this is not a misunderstanding

A waitlist means one thing unambiguously:

• More people want to attend than the event can currently accommodate.

That is stronger evidence of viability than any minimum RSVP threshold.

If people are waiting, the event is viable.

Yet the page still claims the event is short of a required minimum.

Both statements are presented as facts.

Neither is explained.

I am left to reconcile the contradiction.

What’s really happening under the hood

The platform is tracking two unrelated counters and exposing both directly.

1. Minimum RSVP threshold (organizer-facing)

• A number set by the organizer (e.g. “5 RSVPs required”)
• Often used to unlock:
  • organizer tools
  • automated reminders
  • confirmation badges
• Waitlisted people do not count toward this number

2. Attendance capacity (logistics-facing)

• A separate maximum (e.g. 20 people)
• Once reached:
  • additional RSVPs go to a waitlist
• Minimum thresholds do not affect this number

Because these counters are independent, the system allows a state that is logically incoherent to users:

Demand exceeds capacity,
but interest is allegedly insufficient.

That sentence makes no sense to a human — but it is the accurate combined meaning of the UI.

The real failure: unresolved state

A well-designed system would reconcile these concepts automatically.

For example:

• If a waitlist exists, the minimum RSVP requirement is implicitly satisfied.
• Or the minimum is treated as an internal organizer concern and hidden from attendees.

Instead, the platform exposes raw internal fields and leaves interpretation to the user.

This is the definition of a leaky abstraction.

Why the RSVP button becomes suspect

Because the page never clearly states your personal status, the user has to ask:

• Have I already RSVPed?
• If I click this, will I:
  • be added to the event?
  • be put on the waitlist?
  • be told I already RSVPed?

In my case, the only way to find out was to:

• open a separate Attendees page,
• scan lists of names,
• and infer my status by not finding myself.

Only then did the RSVP today button make sense.

A minimal fix that would solve this

No new features required — just clarity.

1. Make personal status explicit

Always show one of:

• You are going
• You are on the waitlist (position #n)
• You have not RSVPed

2. Stop addressing users with organizer metrics

Replace:

“You are 2 RSVPs away from 5 RSVPs”

With:

This event needs 2 more confirmed attendees to reach the organizer’s minimum.

Or hide it entirely once demand exceeds capacity.

3. Make the button describe the outcome

• RSVP (you’ll be added to the waitlist)
• RSVP (spots available)
• Cancel RSVP

No guessing.