Some things just come naturally. Others are more demanding and...complicated. But I think the hard things end up leading to the most rewarding of things. Like studying for a test. Usually (hopefully), all that time and effort turns into the grade that you want.
Example. I have to bike to work. Uphill. My legs are not the strongest they could be (I'm working on my thunder thighs), so it's hard for me to make it. I'm sure it's not a pretty sight, but it's rewarding in the end. Work is air conditioned. Work is soothing (it's routine, my favorite). Work is money that I can then use for better things. So, biking to work is hard, but it is very rewarding. That's a worldly aspect.
Another example. Repentance. Repentance is not an easy process to go through at all. It requires godly sorrow (meaning you're truly sorry for whatever sin you may have committed). It requires forgiveness of yourself. It requires a promise that you won't sin again. But, you are SO rewarded for it. Blessings are poured out upon you. You become capable and worthy of being in your Heavenly Father's presence once again. Isn't that amazing? I absolutely love that! So then why wouldn't we repent, why wouldn't we do that hard thing?
It's not usually very fun to do hard things, but once we've overcome them, we can look back and see the wonder and glory that follows in its wake.