We have this topic in our Blog.
https://chessmood.com/blog/the-game-changer-question-in-chess
If you have any questions, comments or you just liked it, feel free to share your thoughts here.
That quote in the article is from Gandalf in The Fellowship of the Ring =)
These articles 'inspire me to fight one more time'.
As this guy said in TED talk:
https://youtu.be/qvNyo1-AK6o