The control may respond to the point touched rather than requiring a gradual slide. Its normal operation should be checked before treating every jump as a fault.
What the observation means
Wet fingers, objects or a damaged panel can create additional problems, but pressing harder is not a solution. Keep the control strip clear.
A useful next step
Use clean, dry hands under safe conditions and follow the manual. If confirmed inputs remain unpredictable, stop using the affected hob and record the behaviour. Do not cook with an interface that cannot reliably select or reduce power.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.