Why is a child saying ‘Na-na, na-na-na!’ so annoying?

The long-running series in which readers answer other readers’ questions on subjects ranging from trivial flights of fancy to profound scientific and philosophical concepts Readers reply: Why are national anthems almost always orchestral?

Why is a child going “Na-na, na-na-na! ” annoying the world over? I read recently that kids do a version of this in every culture and country. Fred Corbett, London Post your answers…