I think that's the point overall. Building the robots can be done on a factory line, however fixing them will be the only necessary job tasked to humans. And who knows where the humble repairman will be at that point.
And this dream seems to be a possible future for us. A massive class segregation between those who develop new technology and are provided with everything they could possibly need or want, and those who provide everything.
And it's possible. In medieval times a farmer could make enough food to feed his family and a little more on top of that. Taxes were so that the nobles could take that little more off the top in order for the government and soldiery to survive - Luckily enough they had enough farmers for it to work. In comes the agricultural revolution, and then the industrial age, and now a single farmer provides enough for a thousand. Of course the grain farmer makes a pittance from his grain and sells it to the millers who make a pittance making flour and sell it to the bakers, and so continues capitalism.
However, if more and more of the system is automated the pipe dream of one man being able to provide every possible need for an entire city, just because he is the repairman of the robots that keep it all flowing - is a possibility.
However,
The Romans had a massive booming economy, with a huge surplus in money and everyone middle-class and above lived in luxury. However, everyone servant-class and below lived in poverty.
And it was run almost entirely on slave labor.
Slave labor being inhumane, it was removed, and with the beginning of the technology age robotics began to replace it. So this free work is boosting the economy, furthering the goals of humanity and may result in a lot of poverty. When the world is segregated into nothing but the many scientists and the few repairmen, where will the rest go? Remember, the uneducated and socio-economically challenged people (Read: The lower class) are usually the first to get pregnant and have children. Large families are sometimes the best way they can feel a sense of achievement about their life. So where do all these people work? If they aren't intelligent enough to be a scientist and aren't lucky enough to be a repairman, and every other job is automated, where do they go?