People quit jobs...
Some quit because they can no longer handle the demands.
Some quit because of family concerns.
I applied for a church ministry opportunity last year where the man leaving wanted to have the right man in the spot to "take it to the next level". I admire that. Instead of allowing the organization to remain stagnant, he realized his limitations and acted accordingly.
What we see here in John 16 is similar, though very different. Jesus is in no way "less" that the Holy Spirit. Their roles are simply different. Think for a moment about what this meant for Him:
It was better for us, that Jesus suffer and die.
Better for us...
I wonder what we give up or endure for the betterment of others?