This may be a case of kicking a dead dog, but the Queensland Government needs to explain why Citytrain has become so unreliable, as evidenced by this statement on the Translink website this morning:
Train services have resumed after a recent signalling fault.
Up to 30 minute delays across the network for some customers travelling into the City are expected.
For the second time in two months I’ve been turned away from Toowong Station and forced on to the CityCat or bus. Has QR had insufficient resources to invest in regular maintenance? Or is the Government just extremely unlucky there have been two major reliability issues within months of the election?
Queensland Economy Watch 
I am led to believe the first issue was a fair bit of bad luck. It was a failure after many years due to incorrect installation, but the failed part was under a cover and so couldn’t be regularly inspected and had never failed before (ie no history). It failed at Roma St, which affects the entire network.