Disguised Unemployment
  
Yep, even unemployment can take on a disguise, Clark-Kent style.
Disguised unemployment is when unemployment numbers look good. Employment is high. But productivity is still low. Which means all those recent hires aren't actually contributing to productivity. While they're technically working and getting paid, they're not actually doing anything productive (not that it's their fault, to be fair).
In general terms, disguised unemployment includes anybody who is working well below their capabilities. Put another way, it's all of that lost opportunity cost of workers who could be contributing more to the economy based on their skills and capabilities, but aren't...whether it's their decision, or because the jobs just aren't there.
When does unemployment decide to don part of its face with a mask like the Phantom of the Opera? It's pretty common for disguised unemployment to happen in developing countries that have a surplus of workers. With so much available labor, the market can charge lower wages and soak up a lot of those workers, even if that creates more-than-the-necessary-amount of workers hired.