My son has grown up and he often ask me difficult questions.
'Why was Japan National Railways (JNR) disappeared and privatised?'
I told him about the financial difficulty of JNR. But he responded that Yamanote line or Shinkansen carry many people and look profitable, so I explained about the deficit in the lines of rural areas. Besides, I pointed out the inefficiency of public organisation and effect of motorization and airlines.
It is stimulative to have such discussion with my son.