This is a constitution that is designed to grant supreme power into the hands of the military. The constitution grants supreme power to the commander-in-chief, so the commander-in-chief can run the military, the armed forces, as he deems fit. The constitution also grants the power to the commander-in-chief to appoint three ministers in the cabinet and also to appoint 25% of seats in parliament, not only at the union level but also at the state and regional levels. Then they make it difficult to amend the constitution by saying that any constitutional amendment should be approved by a vote of more than 75% of the vote.
Some people say that 75% will be enough if we can get some people in the contested seats, and then we could change the constitution, but it is not true. Even if all 75% of the elected representatives stand together, they cannot win if they are unable to get even one vote from the military, and we all know how the military will vote. They will vote as per the instructions made by their commander-in-chief.
So the 25% is kind of similar to the veto power held by five permanent members of the United Nations.