I argue that consciousness emerged for solving novel problems. Let's imagine a person driving a car. When he is taking the same route to his home, which he usually does, he doesn't have to be consciously thinking about the route; instead, his subconscious brain deals with driving. 

The need for consciousness ( being aware) comes from solving novel problems as they come with patterns that the person hasn't seen or encountered before, or for which no direct decision-making process exists. Instead, he needs to actively think about the problem and communicate with different parts of the brain and gather information, and do processing in working memory, and then make a decision. 

If it is for novel problem solving, why do you have to remember the decision process or remember the experience of something when conscious?

The reason that we remember the experience for a short while is to transfer that novel problem decision-making or experience into long-term memory if that is actually needed. If that is not much relevant, then it won't transfer to long-term memory and eventually be forgotten easily. 

Most of the animals have consciousness, as they have to solve novel problems in day-to-day life, gathering food, and escaping from predators. Simple organisms like plants don't have to have consciousness, as they are rigid and most of the decision-making happens via reflexes.