There is no one answer to it, there are many different factors that affect the decision of different voters. We all have biases, let it be ethnic, sectarian or even intellectual. Most of the time these biases is what affects a voter's decision in an election.
Take Punjab, the biggest province and most of the time the deciding factor in our national elections.
Up till 2010s, before the PTI phenomenon, there were two types of major vote banks here. Pro Bhutto and Anti Bhutto. Pro Bhutto was of course the PPP voters, they loved Bhuttos and were their Jiyalas, there were some urban folks in it but most of this camp was made up of rural population. Why did they loved Bhutto? Roti Kapra aur Makan, that slogan was a real crowd puller.
The Anti Bhutto camp were mostly the urban conservative middle class voters, who were pro Zia and found NS as a continuation of his legacy. This is why PMLN is called a GT Road party, as their power lies in urban centers along the GT Road.
During the Zardari govt the Pro Bhutto voters in Punjab got disillusioned because of the corruption, his friendly attitude towards PMLN, and hence in next election we saw PTI winning a huge chunk of their votes in Punjab but in my personal experience most of the PPP voters stayed home instead and did not take part in the elections.
NS on the other hand was able to still use the Anti Bhutto votebank, remember his speeches during the elections, he was openly saying that any vote to PTI will actually be a vote to PPP and also that PTI is a B Team of PPP.
The next election will be a bit different in my opinion, because NS will require a completely different narrative than what he has been successfully using for past 3 decades. PPP is a non-entity in Punjab elections now, it will be PMLN vs PTI, and he can't use the corruption slogan as well, as that will only hurt his own party especially after recent JIT report.
