Changing in music over time

Have you ever notice how much music has changed over time? I mean if you look at music even just from 15 years ago there is a great difference. Each musical talent brings something of their own to the stage and it adds on and on. it is like one persons choice (in music) can change it completely. musicians (weather they know it or not) help each other out with how they preform, maybe not directly but they do. look at Micheal Jackson for instance, he had a while where he was amazing! He was the king of pop (now i do not care for him or his music but i do respect what he has done for music) after a while though he fell, people actually began to hate him and pop kind of fell for a couple years and wasnt as popular. When he died people began to realize what he had done for music and pop then again shot up and became a lot more popular. Another quick example would be the Back Street Boys, they were one of the first "boy bands" and after them the Jonas Brothers, after them Big Time Rush, and than One direction, all huge "boy bands" and all similar in a lot of ways but do bring their own things to the stage. Over time each generation comes up with a new thing that is foreign to the older generations but greatly impacts the upcoming generations and was greatly influenced by the old generations.