Why would he ask her out if he could get rejected?
Why do people climb mountains when they could die in the attempt?
Why rock climb when you could get injured?
Why would someone use their life savings are take out a loan to start a small business?
The answer in all cases is, for the reward, or said another way, for the satisfaction of success. Getting a date could be the first step in a deep and meaningful relationship. Climbing the moutain or cliff face brings a sense of accomplishment that will last a long time. Owning your own business brings freedom and potentially, wealth. The risk is worth the reward.
Why would someone willfully accept beatings, whippings, insults, abandonment, and ultimately death by crucifixion for ungrateful people. Hebrews 12 says Jesus did all that for "the joy set before him". He endured everything he endured for the reward.
God asks us to participate in the mission of saving souls. He wants us to share the good news of salvation with our friends, neighbors and co-workers. That is scary. That is risky. People will find out who we really are. We may be ridiculed. People may get angry with us.
Or, people may listen to what God says to them through us. People may find something to fill the god-shaped hole inside of them. That would be wonderful. It would fill us with joy knowing that someone who needed God found him.
Knowing this, we should take the risk. We should boldly be a witness for Christ. The reward is worth it.