Why Do Sentient Beings Not Attain Liberation?

Because manas constantly grasps the dharmas perceived by the perceiving-aspect of the ālayavijñāna as self and as belonging to self, it is bound by those dharmas and thus is not liberated. Whatever dharma the ālayavijñāna perceives, it manifests that dharma just like a mirror. After the manifested dharmas are cognized by manas, it takes them all to be self and belonging to self, and thus craving and attachment arise. If manas clearly recognizes that these dharmas plainly all belong to the ālayavijñāna and are not mine, then manas eliminates ignorance, eliminates the self-view of persons and the self-view of dharmas, and attains right view; it no longer grasps these dharmas as self and as belonging to self, and thereby is liberated from all dharmas and becomes a Buddha.