There are a few ways to estimate the number of massive open clusters expected in the disk of the Milky Way, such as the total star formation rate of the Galaxy, or the open cluster mass function extrapolated to include the entire Galaxy. Surprisingly, they give similar predictions: the Milky Way should contain about 100 clusters as massive as 30 Doradus in the Large Magellanic Cloud, and even several clusters with 10 times that mass. Why don't we see them? This talk will first look closely at these predictions and compare that to what we have found so far in our Galaxy. I will then present sophisticated Monte Carlo imaging simulations our group is doing to estimate the selection biases faced by current near-infrared searches for these massive clusters.