At some point people need to be informed. Look at the current visa bulletin for example (points B and C). This bulletin shows the DV allocation for current month and projected for next month. That's the quota and number game. Winning a DV lottery is no way a guarantee to get immigration visa to US no matter how many letters you have received until you get through the consular interview and final number counts. http://travel.state.gov/visa/frvi/bulletin/bulletin_3219.html