Your mass is sitting behind your hands, which is the direction you cannot save. Fingers can stop a fall forwards; nothing stops a fall backwards except getting back over the hands.
What it looks like
The weight is in the heel of the palm and the fingers are doing nothing. The hold ends with the feet coming back down the way they went up, often after a short, urgent arch to try to save it.
Why it happens
A kick-up that stops short leaves you behind balance, and fear keeps you there: away from the fall over the top is also away from the balance point. Closed shoulders do the same thing geometrically — if the arms cannot line up with the torso, the mass never arrives over the hands at all.
What it costs you
It is the shortest handstand there is. Every hold ends the same way, and the fingers — the thing that actually does the balancing — never find out what they are for.
How to fix it
Push through your fingertips and let the body come forward until the fingers have something to do. Practise the bail until falling over the top stops being the thing you are avoiding, and kick up to just past vertical rather than just short of it.
Drills that fix it
Fingertip balance drill
5 × 20s of deliberate small drifts.
In a hold, deliberately let yourself drift forward and stop it by pressing the fingertips. Then drift back and stop it with the heel of the hand.
How Nstand measures it
Nstand measures where your mass sat relative to your hands, in torso lengths and in the direction your chest points. More than 0.15 torsos behind the hands, averaged over the hold, is called weight in the heels.
It is a camera and some geometry. It does not replace a coach, a gym or an academy, it cannot see your wrists, your history or what you are about to land on, and it is wrong sometimes. Handstands can injure you. What you do on your hands is your decision and your risk: warm up, train where a fall is safe, and stop when something hurts.