The answer to this question is:
Radiation
Well,if you don't follow instructions you might make a mistake and mess up what you were supposed to do.Its making a cake,if you don't follow the instructions you could make the cake wrong and it would either not taste as good or it wouldn't come out like it should've.
It's really important to know your audience when you start writing something. For example, if you want to write a dystopian novel, usually teens and young adults read such books, so you want to modify your novel and theme a bit to better suit their interest and understanding. You need to decide on which group of readers you want to write for so that you can adjust themes, motifs, characters, etc.