Why some souls seek reincarnation?

Will you explain more clearly why some souls seek reincarnation and some come back against their will?

There is a law for this, as for all things. Some spirits rebel against it, as some with you rebel against their birth out of the flesh; but all must succumb to this law. When the spirit refuses to think of its new birth into matter, the law takes its course under difficulties. As with you, the good citizen feels no law, only those who wish to rebel.

—Insight