Lord Krishna is called Swayam Bhagawan because he is "Divine Love" and ALL the Avatars of Maha Vishnu is attracted to him.

Bhagawan Sri Krishna is regarded as Purna-Avatara, which means the full incarnation, Avatara is 'Incarnation,' and Purna is 'the full'. He is considered to be a complete manifestation of God, not a partial expression of the Divine Love.

From Shri Krishna, Maha Vishnu manifested and from Maha Vishnu comes all the Avatars, with the exception of Shri Krishna who is Purna-Avatar. He come directly into this world from his abode, Goloke.

The Scriptures say Lord Vishnu has unlimited qualities, among which there are 60 super-excellent qualities. But Lord Krishna manifest with 64 Divine Qualities.

What are those four extra qualities in Sri Krishna?

1.)Roop Madhuri: He is extremely beautiful,attractive and charming form of Sri Krishna.

2.)Murli Madhuri: When He plays the flute, he attracts the minds of everyone.

3.)Prem Madhuri: His Loving pastime as he lovingly play with his devotees.

4.)Leela Madhuri: His attractive leelas he does as a Little Child.

These four extra Madhuris reside in the form of Sri Krishna, which don't reside in other forms, other avatars of God.

My Gurudev, Jagadguru Kripalu-ji Maharaj says,"Sri Krishna has got such an attraction that those yogis who are sitting in samadhi..., He attracts their minds also. What to speak of anyone else, Shankar-ji, who is sitting in Kailash..., even He gets attracted to come and have darshan of Sri Krishna."

Key Note: Remember That there is Only One God, but there manifestation are at different level, like a flower blossoming from a bud to a fully blossom flower.

Maha Vishnu also manifest into three forms to create and maintain the universe:

First form is Kaarnanoshai:creates the material universe by breathing out and when he breathes in, all the universes go back into His body.

Second form is Garbodashai: enters the universe and maintains it.

Third form is Ksheerodashi: enters the heart of every living entity as the Supersoul and is found in every atom; also known as Parmatma.

Animated from Lord Krishna is Brahm, the soure of all power, Brahm is the impersonal power of Lord Krishna which manifest into the Creation, Bramha, the Sustainer, Vishnu, and the Dissolution, Shiva, of the universe.