When something is not enough, it's insufficient. For instance, someone can love you but that is not enough to keep a relationship going. You could also want to succeed in life, but that is not all you need to get there.
For something to work, more
is required for it to be sufficient. A relationship will need more than just love. It also needs trust, faith, compassion, empathy, and good communication. To succeed, you need to work hard, have faith that you will make it, and be persistent.
When there is insufficiency anywhere, things will not work out as they should. This applies to everything in life. Another great example is recipes where the end result would be different if some things lacked in the ingredients. Here is a collection of insufficient quotes to show you a new perspective.