Corolla is most selling car in Pakistan because of xli/gli, the day they go its sales also go down.
As much as ik, Toyota kirloskar motors of India does assemble Corolla in India locally but the compact sedan segment is small there anyway.
Corolla is best selling car in countries where road conditions ain't great and Toyota's general repute is that of producing "ever lasting white goods", there's nothing more to it. In US & Canada, Civic is the best selling compact car but Corolla still occupies the second space just because of that repute despite all reviews telling how boring and basic it is compared to the competition, plus in many countries Toyota occupies a significant commercial vehicle market share with Corolla & Camry, other companies often do not venture in this segment in most countries as they find returns to be low on selling bulk units to these taxi etc operators as ofc the one that bids lowest gets their orders, even fortuner is now running as a taxi in Thailand in addition to Corolla so Toyota does get some sales from stuff like this as well, whole middle East has camrys and corollas running as taxis.