Firing a pot is not drying it. Between 200 and 1000 degrees the clay changes mineral form: quartz flips from one crystal structure to another at 573 degrees, and the whole pot moves on the shelf as it does. Above that, the fluxes melt and the body vitrifies — and if you go too fast, the pot cracks; too slow, and the glaze runs off it.
Water smoking, up to about 200 °C: the last of the chemically bound water leaves the clay, and it leaves loudly. This is the stage where pots crack, because the steam has nowhere to go if the kiln is closed too early.
Quartz inversion at 573 °C: the silica in the clay changes crystal structure and expands by about one percent, and every piece in the kiln moves at once. Then sintering, where the body starts to close up, and finally vitrification, where the glaze becomes glass and the pot stops being porous and starts being a thing you can put liquid in.