Let us consider Ma Saraswathi for this question. The following are some of the sloka and names for the Saraswathi
ॐ शिवायै नमः। Om Shivayai Namah। (125)
ॐ सर्वैश्वर्य प्रदायै नमः। Om Sarvaishvarya Pradayai Namah। (190)
ॐ ब्रह्माण्डाधिप वल्लभायै नमः। Om Brahmandadhipa Vallabhayai Namah। (515)
ॐ ब्रह्मेश विष्णुरूपायै नमः। Om Brahmesha Vishnurupayai Namah। (516)
ॐ ब्रह्मविष्ण्वीश संस्थितायै नमः। Om Brahmavishnvisha Samsthitayai Namah। (517)
It is obvious from the mentions that Saraswathi is parabrahman. She is in the form of Shiva, Vishnu and Brahma. She is moksha vidya.
But whenever we read or hear about her, she is signified as the goddess of knowledge, learning, etc., instead of the complete parabrahman. Even scriptures praise her in these aspects generally.
The name #190 says that she can give any wealth. But, whenever people want wealth, they (generally) pray to Lakshmi even though Saraswathi can bestow wealth.
What is the need or reason for signifying particular aspects of parabrahman even though she can bestow anything and everything?