Question Why ram decrease the frequency when more rams are added.

[Name doesnt matter]

Why ram with more ranks or when installed in a large amount, has less frequency than ram that has less ranks. I know that ram with more rank,stress the imc more but how?
(i know about all the topology)

 

[vov4ik_il]

Are the sticks of the same specifications? It goes by the lowest as you might know...