This is Allah Ta’ala’s decision. He Alone, in His wisdom, knows why.
Non-Muslims do get a chance to accept Islam in their lifetime. Refer below.
And Allah Ta’ala Knows Best
Ml. Imraan Vawda
Your question relates to Taqdeer, the belief that Allah Ta’ala has predestined all affairs from beforehand. Taqdeer is one of the attributes of Allah Ta’ala. Like all His lofty attributes, we, as created beings cannot fathom or comprehend in total this concept. Our intellect is finite and created. Allah Ta’ala’s wisdom and reasoning is infinite and uncreated. Thus, we cannot be expected to totally grasp this concept in our minds.
Allah Ta’ala definitely has a wisdom behind each of His actions. If we cannot comprehend it, it does not follow that it does not exist. It is precisely for this reason that Rasulullah (Sallallaahu Alayhi Wasallam) has prohibited us from delving into this tenet of Imaan. Just as we cannot fully comprehend the actual being of Allah Ta’ala, so, is it impossible to comprehend his qualities, of which one is Qadr (the predestiner).