Repetition is one of the most basic design principles, but it's also one of the most versatile.  Repeating elements can make you feel safe, they can firmly establish brand identity, they can be ridiculous and humorous - or they can make you want to join the party!

Come see how repetition affects our human minds, which crave a certain degree of conformity but reject it when it's too much. 

 

Some links that explain how this works:

https://www.thirdwunder.com/blog/the-importance-of-repetition-in-design/

https://venngage.com/blog/design-principle-repetition/