When two neurons are activated, the connections between them are strengthened. If you repeat the information enough times, the neurons form a “firing trace”. Once the trace is formed, then just starting the sequence triggers the rest of the items, and allows you to retrieve the memory. This is why you need to hear information over and over in order for it to “stick”.

https://www.blog.theteamw.com/2011/03/30/100-things-you-should-know-about-people-94-repetition-changes-your-brain/