Why is Binary Search preferred over Ternary Search?

The following is a simple recursive Binary Search function in C++ taken from here.
 

The following is a simple recursive Ternary Search function :
 

Which of the above two does less comparisons in worst case? 
From the first look, it seems the ternary search does less number of comparisons as it makes Log₃n recursive calls, but binary search makes Log₂n recursive calls. Let us take a closer look. 
The following is recursive formula for counting comparisons in worst case of Binary Search. 
 

 T(n) = T(n/2) + 2, T(1) = 1

The following is recursive formula for counting comparisons in worst case of Ternary Search. 
 

 T(n) = T(n/3) + 4, T(1) = 1

In binary search, there are 2Log₂n + 1 comparisons in worst case. In ternary search, there are 4Log₃n + 1 comparisons in worst case. 
 

Time Complexity for Binary search = 2clog2n + O(1)
Time Complexity for Ternary search = 4clog3n + O(1)

Therefore, the comparison of Ternary and Binary Searches boils down the comparison of expressions 2Log₃n and Log₂n . The value of 2Log₃n can be written as (2 / Log₂3) * Log₂n . Since the value of (2 / Log₂3) is more than one, Ternary Search does more comparisons than Binary Search in worst case.
Exercise: 
Why Merge Sort divides input array in two halves, why not in three or more parts?