As a result, the conditioned reflex fades away? What is the biological meaning of this phenomenon?

Reflexes are unconditioned (those that are from birth) and conditioned (those that are acquired in the course of development). Conditioned reflexes are not transmitted genetically, they help the body adapt to some temporary conditions or environmental changes. Conditioned reflexes are specific to a particular organism. The main difference from instincts and unconditioned reflexes is that conditioned reflexes fade away due to the absence of the stimulus due to which they arose. The biological meaning of this phenomenon lies in the very definition of a conditioned reflex – they appear when necessary (under certain conditions) and disappear when they are no longer needed.