the "counters" against eack MAK product key, indicate the total number of times you "have/can" use/activate that product key.
these counters are not related to how many servers you are licensed to be using at any one time.
MS grant some extra activations, so that you can reinstall/rebuild/relocate/move a few times, and don't have to get extra activation permission.
the extra activations also cater for some server virtualisation, since WS2012 permits some virtualisation and you need to activate each virtual server.
refer Task 1.3: http://technet.microsoft.com/en-us/library/jj134256.aspx
The following information outlines initial considerations that you need to review for Multiple Activation Key (MAK) activation.
MAK is used for a one-time activation with activation services that are hosted by Microsoft. Each MAK key has a predetermined number of allowed activations. This number is based on your volume licensing agreements, and it does not match your organization’s exact license count. Each activation that uses a MAK with activation services that are hosted by Microsoft counts towards the activation limit.
Also, this article (for Office2010 but principle applies):
Also note that if you deploy on-premises KMShost or ADBA, there is no such "limit" to activations, but, you must still ensure you are correctly licensed for the total number of running servers.
(Please take a moment to "Vote as Helpful" and/or "Mark as Answer", where applicable.
This helps the community, keeps the forums tidy, and recognises useful contributions. Thanks!)