That depends on what you mean by efficient. Let's say you want to build a road that connects 12 houses. You can do that without the government. You just need e

That depends on what you mean by efficient. Let's say you want to build a road that connects 12 houses. You can do that without the government. You just need everyone to agree on who contributes what, who you hire to do the work, what happens if something goes wrong, who else is allowed to drive on the road, how maintenance happens, who polices the rules, and so on, and so forth. This does occasionally work out in real life, but mostly people bitterly argue over the whole thing and it never happens. Having a government set some sort of policy and doing the planning is usually far more effective, even if it pays more than is necessary for the actual work that gets done. The government may pay more per mile of road, but the road has a higher odds of getting built.