I suppose it happens in other Australian cities, train lines disrupted. It seems to happen very often in Melbourne. Often there is a statement from the appropriate public transport company that buses are replacing trains on whatever train line that has failed.
Invariably there are complaints from passengers that the replacement bus service does not not turn up, or the number of buses that turn up to replace a train is inadequate. Passengers are justifiably very annoyed, but should they really be annoyed about an insufficient bus replacement?
Off peak maybe it is not so bad, but what are the logistics of getting buses to replace trains at short notice at peak times? I don't know but here are some thoughts.
There must be spare buses. No, I shouldn't think so. Not in peak time. Why would a private bus company have buses sitting around depreciating and not being used? There are also standing costs of having buses, such as registration and maintenance whether they are used or not. It would be irresponsible to the bus company shareholders to be so profligate. Perhaps there are buses scheduled for maintenance that could be deferred, or I would imagine each bus company would have a couple of spare buses of their own to cover their own emergencies that could be used. But how many buses are needed to replace a train that might have 800 people on it and then do this again ten minutes later and then ten minutes later again? The answer can only be many.
What about drivers to drive the possible spare buses? They are sitting around in the bus depot in peak times and getting paid for doing nothing? Most unlikely. I expect drivers who are not at work are called at home and offered overtime. Some may say yes, some may so no and I hardly think they can be ordered to work overtime, let alone at such short notice.
I can only draw one conclusion. If a train line goes wrong and you hear that there is a bus replacement service, make alternative arrangements, as there is no way a replacement bus service can offer anywhere near a satisfactory replacement service unless the problem lasts more than a day, and even then it could not really offer anything like a normal train service.
As Daniel Bowen has suggested in the past, if you have a local bus service, work out your alternatives before something goes wrong with your train service.
So if a replacement bus service can never be satisfactory, what should be of the highest priority is to ensure train lines don't go wrong. It may be that the media is faster and more comprehensive, not necessarily more accurate, with reports of train problems, but to me it feels like the train service is deteriorating, so far as disruptions go.