I did my PPL training in the States. On my pre solo flight my instructor said, "Give me a good circuit and you can go solo."
Well, on the take off, something on seat lock gave way and since I had just rotated, my seat went right to the back and as I had my hand on the controls so the aircraft pitched up towards a power on stall. Thankfully, my instructor was next to me and took control.
We landed, the seat got fixed and I did not go solo for another hour or so. However, I learnt an important lesson there and when I did go solo, it was fantastic.