But when the infrastructure is there, it's better to have trains full of passengers than empty. There are 3 daily flights between Amsterdam and Brussels. It takes about 30 minutes by plane. By car it's about 2h15. By highspeed train it's 1h50. There is absolutely no justification to use the plane. The time you take to register and board the plane nullifies any time advantage. The only advantage is the cost and the pleasure to see the landscape from above.