So, I am really confused about the significance of initial count?
One important point that may help here is that Wait decrements the semaphore count and Release increments it.
initialCount is the number of resource accesses that will be allowed immediately. Or, in other words, it is the number of times Wait can be called without blocking immediately after the semaphore was instantiated.
maximumCount is the highest count the semaphore can obtain. It is the number of times Release can be called without throwing an exception assuming initialCount count was zero. If initialCount is set to the same value as maximumCount then calling Release immediately after the semaphore was instantiated will throw an exception.