Result of withdrawing bus routes parallel to train routes

What does the recent breakdown of the North South Line and the East West Line tell us? It was a wrong call to withdraw bus routes that duplicate the train routes. When the line is down, there is absolutely no way that a person can get home and all the buses deployed is of no use because there are just too many people stranded at the same time. 

Don't go comparing with other countries having train breakdowns because I know for the fact that at least one of the countries, Japan, has parallel train routes and their railway is designed in such a manner that they can bypass certain stations if need to. 

Immediate need is to reinstate bus routes that run parallel to the train routes. That would also incentivized the train operators in doing preventive maintenance properly, not corrective maintenance.