The reason was simple at that time (and even today) as an STATE we were pursuing the policy of integration of alienated and disgruntled segments of the society to the national fold, this policy is a logical outcome of the conditions and sufferings which Pakistan as an state and different elements of its nation faced over the period.
This policy has shown results in Baluchistan, Punjab, Karachi even in KPK and FATA, PTM is just a minority segment of the society and politics of KPK just because of them we could not change the entire policy overnight.
Now we all sharing the same concern about the PTM as it seems they have wasted the given opportunity so they may soon face the same fate as of TLP or MQM
We after the independence as an STATE for the first time have realised that inequality, political and social injustice would certainly end our survival in the future, so TLP and PTM, MQM type political factors or TTP, BLA/BLF type hardcore terrorist will eventually lose their grounds with the passage of time IF we start addressing the real concerns of common man regarding the economy and peace in the country.