Abhijit Naskar said this quote

Nanak wanted to preach people that God loves both the Hindus and the Muslims the same way. Believing in his spiritual encounter, he wanted to eliminate the distance between the Hindus and the Muslims by teaching the words of equality and One God. But just like usual, he ended up forming yet another religion which became more and more hardcore with its own rituals and regulations in the hands of the subsequent nine Gurus.