Answer:
1. In life we face situations where we need to choose only one way/solution, but there is alot of choices/thoughts/what ifs that makes us think what is the right choice.
2. We can say we did when the result doesn't harm somebody or something. And if so, It harm them in a good way or it changed them.
3. With prayer. Ask God's guidance and also be confident in whatever you choose. Hanabi (a hero from ML says, "Make the right decision or YOU MAKE THE DECISION RIGHT."
4. Because we care and worried about something. Or because we want a result just as we expect it to be.