You're standing in an office lobby, watching the elevator display. It says the average wait time is 45 seconds. But you've been here at least a minute, maybe two. The doors finally open, and you step in thinking: that sign is definitely wrong.
Here's the thing—the sign might be mathematically accurate. The problem isn't the elevator or the calculation. It's that "average" doesn't mean what most of us think it means. This simple frustration reveals something profound about how statistics can tell the truth while completely missing your actual experience.
Mean vs Median: Why Average Wait Time Doesn't Match Typical Experience
Imagine an elevator that serves ten people throughout an hour. Nine of them wait 20 seconds each. One unlucky person waits 5 minutes because the elevator was stuck on another floor. Add up all those waits: 180 seconds plus 300 seconds equals 480 seconds total. Divide by ten people, and the average wait time is 48 seconds.
But here's what actually happened. Nine out of ten people waited only 20 seconds. The "average" of 48 seconds describes almost nobody's real experience. This is the difference between the mean (the arithmetic average) and the median (the middle value when you line everything up). The median wait was 20 seconds—much closer to what most people experienced.
When a few extreme values pull the mean away from typical experience, statisticians call this a "skewed distribution." It happens everywhere: average income, average home prices, average response times. The mean gets dragged toward outliers while most people cluster somewhere else entirely.
TakeawayWhen you hear "average," ask yourself: average of what kind? The mean can be technically correct while describing almost nobody's actual experience.
Psychological Time: How Uncertainty Makes Waits Feel Mathematically Longer
There's another twist. Even if the median wait really is 45 seconds, it might genuinely feel longer. Research on time perception shows that uncertainty stretches our experience of duration. When you don't know how long something will take, each second registers more intensely than when you're occupied or informed.
Think about watching a pot of water boil versus scrolling your phone for the same two minutes. The watched pot feels eternal. This isn't just psychology—it has mathematical implications. If you asked people to estimate their elevator waits, their answers would cluster higher than actual measured times. Surveys about wait times aren't measuring the same thing as stopwatches.
This creates a genuine puzzle for designers. Do you optimize for actual wait time or perceived wait time? Some buildings install mirrors near elevators not to reduce waits, but to give people something to do. The math stays the same, but the human experience changes.
TakeawayOur perception of time isn't a reliable measuring instrument. Uncertainty acts as a multiplier, making identical durations feel completely different depending on context.
Optimization Paradox: Why Mathematically Efficient Systems Can Feel Inefficient
Here's where it gets really interesting. Engineers often optimize elevators to minimize total wait time across all users. This sounds perfectly reasonable until you think about what it means. The system might let you wait an extra 30 seconds if it saves three other people 15 seconds each. Mathematically, the building wins. But you don't experience the building's total—you only experience your wait.
This creates situations where the optimal system feels worse than a less efficient one. A perfectly fair elevator that makes everyone wait exactly 40 seconds might score worse on average than one where most people wait 30 seconds and a few wait 90. Yet the "worse" system would feel better to most individuals.
The same tension appears in traffic flow, hospital queues, and customer service lines. Mathematical efficiency often conflicts with felt fairness. Understanding this doesn't make your wait shorter, but it does reveal something important: the numbers aren't lying to you, they're just answering a different question than the one you're asking.
TakeawayOptimization always serves a specific goal. When a system feels frustrating despite being "efficient," ask: efficient for whom, measured how?
The elevator mystery isn't really about elevators. It's about recognizing that numbers always come with invisible assumptions. "Average" can mean different things, perceived time differs from clock time, and system efficiency doesn't equal individual satisfaction.
Next time a statistic surprises you—wait times, salaries, test scores—pause before deciding it's wrong. Ask what kind of average, measured how, optimized for what. The math might be perfect. It might just be answering a question you didn't ask.