Pakistan is one of the two successor states to British India - India being the other one. India, by the standards of developing Asian countries, is a success story as far as functional democratic institutions and political stability. It's by and large a more ethically-challenged version of Westminster. Pakistan, by comparison, has been run more like a Central American banana republic or a post-monarchical Middle Eastern state. It's had a revolving door of reactionary military strongmen, occasionally punctuated by a populist civilian leader like one of the Bhuttos or their allies.
Both countries became independent with the same democratic and civil institutions - structures that had been put in place during British rule. So why did India end up being so much higher functioning than Pakistan? How did Pakistan end up having more in common with its neighbor to the west than with its neighbor to the east?
Well for one thing, India had something like 90% of the subcontinent's industry before the partition, and much of the financial reserves from the colonial government. Not to mention the fact that there were already several thriving major cities in India...
Also keep in mind all of the refugees who were resettled n Pakistan in the years after the partition. There was a lot of violence and chaos in that process.
An unfair comparison, really.