There is a common Pakistani theory behind it.
You will agree with me,that the 1965 war started exactly the same way the Kargil war started right? i.e,they push in jihadis/regulars to attack Indian posts in Kashmir across the LOC.Now the Pakistani generals thought,since the fight is around the LOC which is not International-border,Indian reaction will be localized.
But,in my opinion only a fool will think that the enemy will respond the way it suits him the best.We consider Kashmir to be integral part of India,an attack on India-held Kashmir is tantamount to an attack on India's sovereignty.So,we have no problem in retaliating,in places where the enemy is weakest.Afterall military strategies are not planned with hot air pumped inside the head right?
I just could not believe that the Pakistani generals will be dumb enough to repeat the same mistake of 1965 in 1999,during Kargil war.Thankfully,the rebels were repelled much easily this time and the Kargil war did not get escalated into a full-scale war.Had it been prolonged any longer,India would have opened a second front.The Indian Navy was already preparing for a blockade of Karachi port.