The quote from 2015
"But the true worth of our apostolate is measured by the value it has in God’s eyes. To see and evaluate things from God’s perspective calls for constant conversion in the first days and years of our vocation and, need I say, great humility. The cross shows us a different way of measuring success. Ours is to plant the seeds: God sees to the fruits of our labors. And if at times our efforts and works seem to fail and produce no fruit, we need to remember that we are followers of Jesus… and his life, humanly speaking, ended in failure, the failure of the cross"
Basically the cross shows us that human perspective may call something a failure when actually without it the greatest triumph is not possible. That we must not look at it as men see it because men will see it as a failure...they even saw the cross that way and it was exactly the opposite. The Lord says in Scripture that He does not see as man sees. That is exactly what the Pope is saying.