The gluten had not been given time to relax
Very commonKneading arranges gluten into an ordered, tensioned network. Immediately afterwards that network behaves elastically: stretch it and it stores the energy and returns. Given time at rest the bonds progressively rearrange into the stretched configuration, so the dough becomes extensible — it holds the shape it is pulled into instead of springing back. Nothing about this is a strength problem, which is why adding flour, adding water or kneading more all fail to fix it. The only variable is time.
What to change
Rest the dough, then try again
Cover the dough and leave it fifteen to twenty minutes, then stretch again. If it still fights back, rest it again — a cold dough straight from the fridge may need an hour to come to temperature as well as to relax. Stretch from the centre outward and let gravity do part of the work rather than pulling against the resistance.
Pizza dough, pasta, and any pastry that shrinks back as it is rolled.
Trade-off: Time, and a dough left far too long will over-relax and tear instead — the fix has its own opposite.