fadness
A thing that starts off like a firework, then it dies and nobody even remembers it.
The fad of wearing hats inside was big for a month. Then no one wore hats inside. It was sad.
My friend started the fad of spelling everything backwards. It was cool for a while. Then he spelled my name wrong. It was over.
The fad of people doing the 'dab' was everywhere. Then it was gone. No one remembers it. It was like it never happened.