In Elder's Quorum today, the teacher used a quote from Neal A. Maxwell about foreordination.
This is what Elder Maxwell said, "When in situations of stress we wonder if there is any more in us to give, we can be comforted to know that God, who knows our capacity perfectly, placed us here to succeed. No one was foreordained to fail or to be wicked. When we have been weighed and found wanting, let us remember that we were measured before and we were found equal to our tasks; and, therefore, let us continue, but with a more determined discipleship. When we feel overwhelmed, let us recall the assurance that God will not overprogram us; he will not press upon us more than we can bear (D&C 50:40).
The doctrine of foreordination, therefore, is not a doctrine of repose; it is a doctrine for the second-milers; it can draw out of us the last full measure of devotion. It is a doctrine of perspiration, not aspiration. Moreover, it discourages aspiring, lest we covet, like two early disciples, that which has already been given to another (Matthew 20:20–23). Foreordination is a doctrine for the deep believer and will only bring scorn from the skeptic."
The parts I underlined really got me thinking about how each of use face and respond to challenges. According to this doctrine, we know we've been foreordained to the callings that are being extended to us today. We were foreordained to these callings according to how we exercised our agency in the pre-existence. Armed with the knowledge of these two things, we know we accomplished much before this life and we know we can accomplish much in this life. Consequently, we know we can meet and beat any challenges given to us in this life. And knowing that, at least for me, gives me great comfort and motivation.
Source: "Meeting the Challenges of Today" by NEAL A. MAXWELL