Actually Pashto has two accents one Pakhto and other is Pashto. there for some people pronounce "Sha" and some "Kha"

dear brother, good question. I can tell you that in Pashto we have mainly three accents, 1-east (Peshawar and east provinces of Afghanistan) accent - which pronouce- kh- Kha- good 2- central (central provinces of Afghanistan) accent- between kh and sh- like the pronounciation of V letter in English- can not shown in writing- But I must pronounce it physically to you on MIC. 3- Southern (Southern provinces of Afghanistan and Queta ) accent- - sh- sha- good So there is no reason to ask why they pronounce like this and why they pronounce like that. I hope you accept this. Thanks- Manana Akhtar