Your probably right. Hindustan, Pakistan and Bangladesh constantly compete with one another to become the world's largest ship scrappers... a big buisness offcourse.
The Type-23 is a good ship - it forms the heart and soul of the Royal Navy. 50% of the frigates/destroyer class of ship Britain uses are Type-23. The ships were constructed between 1987 and 2000.
But quality comes at a price. To run a single Type-23 frigate for a year costs Britain over 1.5 billion rupees (16 million pounds)
That means as well as the cost of the 3 ships, Pakistan would be taking on a 4.5 billion rupee cost per year thereafter.
This may come as a bit of a suprise to you but ALL warships cost money to run. That cost of running a warship includes things like wages, food, fuel, and training, most of which will propably cost less in PN service.
The Type 23 will give the PN something it has never had before - a genuine multi purpose warship that is equally capable of Anti-air, Anti-ship and Anti-Sub operations. Until now, most of the PN warships (Type 21, Leander, Garcia etc) have all been primarily for anti-sub operations with a secondary anti-ship capabilty. In all likelyhood, they will be more capable than the F-22P frigates the PN is acquiring from China