How do you get selected to be a Chief in the Navy? Well, its not by luck or chance, or because the selection board feels obligated to fill all the quotas in a particular rating.
Unlike E-4 through E-6, your chances of advancement are not based only on your exam & evaluations (FMS) and the quotas for advancement within your rating. When you go up for Chief, you will be going before the selection board. This is the only promotion in the Navy, for either enlisted or officers, that you will not only have to take an advancement exam, but also go before a selection board. If your FMS is in the top 60% of your rating, you will be selection board eligible. However, the board does not promote personnel to meet quotas. Every year, there are quotas that are left unfilled in some ratings. Even though there were enough board eligible E-6's, not enough of them had the qualities and potential that the selection board felt was necessary to fill the role of the Navy Chief.
Alternately, there are many ratings where the quotas are low and the competition is stiff. Many E-6's are eligible, yet only a few can be selected. It isn't easy being one of the top E-6 for your rating in the whole Navy, but someone will be!. Why couldn't it be you?
This website will provide an overview of the crucial factors that can increase your chances of being selected as a Navy Chief.