An indicator can show availability, progress or a selected option depending on the model. Its meaning should not be inferred solely from the shape of the symbol.
Understanding this situation
Check the complete display and manual, especially if a load finished washed but never dried. A progress icon lighting during one stage is different from an option that guarantees a later stage has been requested.
A useful next step
Note the programme and actual sequence. Before the next safe suitable load, confirm the full selection using the instructions. Do not assume a failed heater when the appliance may not have been commanded to dry at all.
Manuals and supporting guidance
Model-specific instructions take priority. These references support the practical principles discussed here; they do not diagnose your appliance.