[skybrian]

From an economics point of view, an unnecessary job is inefficient not because it gives people money (they can spend it efficiently on themselves), but because it wastes people's time when they could be doing something else. (Not to mention other wasted resources.)

Social security is efficient because it doesn't have this problem.

[Nasrudith]

There are two sorts of efficiency percentage and wisdom - one can heat their house at greater than 100% efficiency by burning money and priceless.

However you really shouldn't be using them that way since there are far better uses for the value.