Here is a scene I see constantly. A man wakes up. Before his feet hit the floor, before coffee, before a window, he reaches for his wrist or his phone and checks last night’s score. Sixty-two. Poor. Light sleep high, deep sleep low. He had felt fine thirty seconds ago. Now he feels tired.
Read that again, because it is the whole problem in one motion. He felt fine. Then a device told him he had slept badly, and he believed the device over his own body, and the verdict became true on contact. The number did not measure his tiredness. The number created it.
I do not track my sleep, and I never will. Not because I do not care about sleep. Because I care about it too much to let a wrist tracker grade something it cannot measure, against a standard that does not exist, in a way that makes the thing worse. Let me take those three apart, because each one is a quiet con.
Eight hours was never your number
Start with the standard everyone is chasing. Eight hours.
Eight hours is not a law. It is a rough average, pulled from a range. The major sleep bodies recommend something like seven to nine hours for most adults, and the word that matters in that sentence is range. A range is not a target. It is a band wide enough to hold most people, which means it was never aimed at any specific person, including you. Your need sits somewhere in there, or maybe just outside it, shaped by your genes, your age, your training load, and the season of your life. The idea that there is one correct number and you either hit it or fail is a category error. You took an average meant to describe a population and turned it into a personal pass-fail line.
And it gets shakier when you look at the stages. The trackers do not just grade total sleep now. They grade your deep sleep, your REM, your sleep latency, your efficiency, and they show you little targets for each. There is no validated ideal amount of time to spend in each stage. The sleep researchers themselves say so plainly. The amounts vary between people, and there is no perfect number to hit. So the device is handing you targets that science has not established, and you are losing sleep trying to reach them.
The instrument is guessing
Which brings us to the second con. The tracker cannot actually measure what it claims.
A wrist wearable does not see your brain. The only way to truly stage sleep is to measure brain waves, which happens in a lab with electrodes on your scalp. Your watch infers sleep from movement and heart rate and makes its best statistical guess about what stage you are in. Sometimes that guess is reasonable for total sleep time. For the stage breakdown, the deep-versus-REM-versus-light split it shows you with such confidence, it is far less reliable. The clinicians who study this say it directly. These are not medical devices, and their accuracy is always suspect.
So sit with the full picture. You are being graded, every morning, by an instrument that is estimating, against a standard that does not exist, for stages it cannot reliably see. And you are trusting that grade over the one source that actually knows how you slept, which is you, lying there, noticing whether you feel rested.
There is a name for what this does to you
Here is the third and worst part. Chasing the perfect sleep score does not just fail to help. It actively makes sleep worse, and the effect is well enough documented that it has a name.
In 2017 a group of sleep researchers coined the term orthosomnia. Ortho means correct. Somnia means sleep. They named it deliberately after orthorexia, the unhealthy obsession with eating correctly, because they were watching the same psychology play out in a new arena. They kept seeing patients who came in convinced they had a sleep disorder, not because of how they felt, but because of what their tracker told them. They believed the device more than their own experience and more than their doctor.
And the mechanism is cruel, because sleep is the one thing you cannot force. Effort is the enemy of it. The harder you try to sleep, the more awake you become, because trying is a form of arousal and arousal is the opposite of sleep. Now hand an anxious high performer a nightly score to optimize. He starts treating sleep as a project. He goes to bed straining to earn a good number, which raises his arousal, which wrecks the very sleep he is trying to perfect, which produces a worse score, which raises the anxiety. The tracker built a loop, and the loop runs on the exact effort the device encouraged.
There is a second layer for the executive specifically. A poor score in the morning is read as a forecast. A bad night must mean a bad day, less focus, worse decisions, a workout to skip. So he expects to feel terrible, and expectation is powerful enough to deliver. The number does not just describe the day. It writes it. A man can sleep perfectly well and ruin his Tuesday because a wrist told him he didn’t.
What I do instead
I judge my sleep the way humans judged it for two hundred thousand years before the watch. By how I feel.
The only sleep metric I trust is the one that runs all day. Am I clear and steady, or am I dragging and foggy by mid-morning? That signal is more accurate than any score, because it is the actual outcome the score was only ever trying to predict.
If you are going to track at all, look at long trends across weeks, never the nightly grade, and never before you have gotten out of bed and assessed how you actually feel first. Let your body file its report before you let the device overrule it.
The things that genuinely move sleep are upstream of any number, and they are boring. Light in your eyes early in the day. Darkness and cool air at night. A nervous system that has come down from the day before you lie down, instead of one still running at full speed. Consistent timing. None of those require a score. All of them require attention to the foundation instead of the metric.
The real problem is upstream of the bedroom
If you wake unrested night after night, the honest answer is usually not a mystery and not a disorder. It is that you never came down.
A body falls asleep well when it shifts out of the day’s fight-or-flight gear into the rest-and-repair state. That shift is not a switch you flip at 11pm. It is a slope you walk down across the evening. The executive’s problem is that he sprints until the last possible second. Calls until dinner. Email after. A bright screen in bed pouring light and stimulation into a brain that is trying to power down. A glass or two of wine to manufacture a feeling of relaxation that is not relaxation at all, because alcohol sedates you and then fragments the back half of the night as it clears. He arrives at sleep still in top gear, then wonders why the engine will not idle.
So he falls asleep wired. And sleep entered from a wired state is not the same as sleep entered from a settled one, even when the hours on the clock match. The body does its repair work poorly when it goes under in a state of alarm. He logs his eight hours and wakes feeling like he logged five, then blames the number, or reaches for the tracker to confirm the failure, when the failure actually happened hours earlier, in how he spent the evening.
This is why the tracker is not merely useless but actively misleading. It aims your attention at the wrong place. It has you fiddling with a readout while the real lever is the slope you refuse to walk down. No score will fix an evening spent at full throttle. Only the evening will.
And the fix is unglamorous, which is exactly why it works and the gadget sells better. Light in your eyes within an hour of waking, which sets the internal timer that releases you into sleepiness roughly sixteen hours later. Real darkness and cool air at night. A hard stop on work and screens with enough runway before bed for the slope to actually descend. Consistent timing, because the body craves a schedule far more than it craves any single perfect night. Do those few things and sleep tends to take care of itself, no number involved.
The calibration
Sleep is a foundation. It sits at the bottom of the stack with movement and food and light. Foundations are not things you optimize. They are things you get right and stop measuring.
The sleep score took the most natural process your body owns and turned it into a performance with a grade. And the moment sleep became a number you chase, you recreated the exact trap that catches the step-counters and the macro-trackers and the men who check their readiness every morning before they have even stood up. You are managing the metric instead of living in the body. The anxiety just moved into the bedroom, which is the one room where anxiety does the most damage.
If you wake up unrested, the tracker cannot tell you why and cannot fix it. The why is almost always the wind-down you skip, the stress you carry to bed, the screen you fall asleep to, the wine, the inconsistency, the nervous system you never let switch off. Those are the levers. The score is just a noisy readout sitting on top of them, and worshipping the readout is how you end up too anxious about sleep to sleep.
Take the watch off at night. Ask your body how it slept. It was answering that question long before anyone sold you a device to answer it for you, and it was telling the truth.
This newsletter is where I take one of these apart every week. The numbers you are chasing, the devices grading you, the optimizations that quietly became the problem they promised to solve. Subscribe if that is useful to you. Don’t if it isn’t.
P.S. None of this is medical advice. Real sleep disorders exist, and if you snore heavily, stop breathing in the night, or have battled genuine insomnia for weeks, see a doctor, the gold-standard treatment for chronic insomnia is a specific therapy, not a tracker. The point here is narrower. The grade on your wrist is not the same thing as your sleep, and confusing the two is its own problem.