16GB is not 16GB. Its 14.9GB when hardware manufacturers are involved.
A true GB is 1 Byte, x1024 x1024 x1024. That's what all software reports it as.
Hardware manufacturers (HDD, SD etc) think differently. They use Decimal...
1 Byte x 1000 x1000 x1000.
So if an SD card is 16 GB, divide it by 1024 (3 times) then multiply it by 1000 (3 times) and you get its true capacity.
So the emmc that the s 3 uses for internal memory is 14.9GB, partitioned for /system 1.5GB, /cache 1GB and /sdcard 11.35GB then the rest is used by all the smaller partitions like recovery and what not.