A scholar writes a book putting into it all the knowledge he has acquired over a lifetime. However other scholars generally endowed with thewhat does he know psychology refuse to go through it.
The bestseller variety of (modern) books soon go out of print at and rarely see the light of the day again.
This book certainly does not belong to either of the categories. It is just an ordinary work meant for the ordinary devotees but aimed at rousing their curiosity to know more about an extraordinary person (i.e. Sri Ramakrishna).