Remember the Sloka of Shrimad Bhagbat Gita wherein Lord Krishna said to Arjuna-
Yada Yada Hi Dharmasya Glanirbhabati Bharata,
Abhyuthanam Adharmasya Tadatmanam Srujamyaham.
Which means that, whenever the evil / unrighteousness increases on the earth, GOD descend to establish the principles of righteousness ( morality) and to protect the good from the onslaught of evil / unrighteous. This is the main activity of the GOD that HE punishes the EVIL.
But the SADGURUS or the PERFECT MASTERS or QUTABs have a different mission whenever they descend on the earth. They never administer punishments to any being ;rather Sadgurus make them pure by constantly giving them such experiences in life which enables them to realize the existence of GOD and prevent them from adopting the path of evil deed. This is the main feature or you can also say , a distinctive advantage, of Perfect Masters over the God.They act like the kalpa vriksha( wish fulfilling tree) which not only gives fruits but also shelter to all.
The mission of Sai Baba is to awaken man to his true self and inherent divine nature. He wanted to lead them to salvation by saving them from delusion and ignorance. He stands there eternally to help out and give solace to His children who are bruised with the miseries of this world through the passage of centuries. Thus His sacred mission is to awaken, transform and comfort His children. These are the visible acts of Baba. But He also had a much bigger role to play in the administration of the Universe – in its creation, sustenance and destruction. He saw God in every living being. It was His duty to take the created to the creator – i.e. to evolve human beings to the state of God – which is their real self (Guruji Shri C. B. Satpathyji).
It is amazing that though He is not present in His physical body, ever increasing number of people hear and experience the same blessed, intimate and powerful assurance- ‘Why fear when I am here!’
Hence we can call SHIRDI SAIBABA as karunavatar (all merciful compassion incarnate )because HE is here to bestow his grace and compassion on us and make us internally pure .