After a Liberal-led coalition was elected in 2013, that party looked for ways to contain costs and speed up the rollout. They focused on what in the telecommunications industry is called “the last mile” — the wires that connect a home or business with the broader network. While the National Broadband Network initially envisioned high-speed fiber connecting homes and businesses directly to the network, the Liberal-led effort compromised by connecting them with existing copper wire — basically, the same technology used in the earliest days of the telephone.

The result, critics say, was slow speeds that still did not stop rising costs.

“Australia had an aggressive, forward-looking, visionary government project to build a fiber network,” said Mike Quigley, who was chief executive of the project until 2013. He added, “that opportunity’s been absolutely lost because of bad judgments, ideologically and politically driven.”

A spokeswoman for the Liberal Party said that under its stewardship, the initiative was connecting more new users than the Labor Party ever did. But neither party placed fixing the internet high on their campaign platforms in national elections last year, perhaps indicating how difficult the problem will be to solve.

Average speeds have more than doubled since 2013, according to Akamai, but other countries are connecting their populations faster, meaning Australia’s lag with the rest of the world has grown. Big businesses can opt to pay for fast connections, but the cost can be considerable for smaller companies.

GO1, an education technology company near Brisbane, spent about $22,000 on a speed upgrade in September 2015. It now pays nearly $1,000 a month for its high-speed, 100 megabit connection. “As a software company, our two main costs are internet and staff,” said Andrew Barnes, the chief executive and co-founder. “If the former was lower, then we have more to spend on building up the team.”

Mr. Barnes said that employees in Ho Chi Minh City, in Vietnam, had far fewer issues joining the company’s weekly webinars.

“Vietnam’s one of those countries where you look out the window and the telephone wires are just a mess,” he said. “But somehow, despite the obvious infrastructure problems, the internet there is much, much better.”