My best way to explain why I carry a firearm every day, everywhere legal to do so is my own personal experience. Nonetheless, my experience could be an outlier, rather than be typical.
Thus, I am going to suggest three books.
"Facing Violence: Preparing for the Unexpected" by Rory Miller. This highly awarded book is a rewarding read. You will learn valuable lessons without getting your face stomped, stabbed or shot.
After that, "Straight Talk on Armed Defense" by Massad Ayoob. Excellent advice from self-defense experts, lawyers and psychologists.
Last is Tom Givens' "Concealed Carry Class". If you carry a gun, plan on carrying a gun or just considering that possibility, read this book.
There is much you should know before you head out of your front door armed. You had better have a full understanding of the laws where you live on being armed and the relevant self-defense statutes. You need to have a good understanding of the psychology of violence and violent criminals. Understand that they simply do not think like you do. You absolutely must have excellent awareness. Especially in transitional spaces, where most violent crimes occur. You must be thoroughly trained in the safe and correct use and deployment of your firearm. There is an enormous amount to learn. Frequent training is essential. Not just shooting a box of ammo at a range now and then... Another factor... In Florida, there have been well over 1 million CCW licenses issued. However, less than 10% of licensed civilians carry a firearm daily. Why? Inconvenient, uncomfortable, clothing choice limitations, loss of interest or simply lazy. Let's face it, carrying a firearm IS a lifestyle change. Some folks get their license simply to avoid the three day waiting period for firearm purchases. Me, I carry every day.
So, should you decide to carry a firearm, don't be a liability to your community. Get proper training. Exercise good practices. Be an asset to the community and law enforcement. Leave your ego at home. Remember that with rights come responsibilities. With regard to your right to carry a firearm, you have the responsibility to do so safely and with wisdom.