It is because AGL like most large Australian businesses are government sanctioned criminals.
The government is so upset about kids throwing rocks through windows in Alice Springs ...yet that sit in the board meeting where the plans are made to allow our large energy companies to throw bricks through the front doors of every Australian.
The sell a product before they have the infrastructure to provide the product, they offer reduced rates for those that complain, lose a few customers of those that realise they are incompetent by design.
It is not by accident that AGL spends majority of its money on signing up now customers rather than resourcing a technical support team, with the skills to provide technical support.
You don't have to disappointed people AGL, you have the market share to do and be better...but you are not encouraged to.
I expect higher prices for less services, all with large government ticks,so we can pretend they competent.