Clause 3 – How to understand the definition of “self-resetting thermal cut-out”

self-resetting thermal cut-out: thermal cut-out that automatically restores the current after the relevant part of the appliance has cooled down sufficiently

In the definition there is a clear mention, when the temperature is cooled to a certain degree, in fact, its intention is to control the temperature is not too high, when the temperature is too high, the thermal cut-out opens the circuit or reduces the current, these two means will reduce the heat, when the heat is down, the temperature’s also down, the thermal cut-out will automatically restores the current.
A common type of self-resetting thermal cut-out is the thermal protector used in fan motors, as shown below.