The hired hand runs away because he’s working only for the money and doesn’t really care about the sheep.
“I am the good shepherd; I know my own sheep, and they know me, just as my Father knows me and I know the Father. So I sacrifice my life for the sheep. I have other sheep, too, that are not in this sheepfold. I must bring them also. They will listen to my voice, and there will be one flock with one shepherd.
“The Father loves me because I sacrifice my life so I may take it back again. No one can take my life from me. I sacrifice it voluntarily. For I have the authority to lay it down when I want to and also to take it up again. For this is what my Father has commanded.”