A rapid temperature change can stress hot materials and create a burn or damage hazard. Cooling should follow the appliance instructions.
What the observation means
Water can also run towards controls or electrical openings. A surface that looks clean may still contain substantial stored heat.
A useful next step
Switch off appropriately and allow safe cooling, keeping people and unsuitable items away. If an accidental splash is followed by a crack, stop using the hob and seek assessment. Do not continue heating to see whether the crack spreads or cover it with a mat.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.