A sense of achievement. Horse shows are all about setting and achieving goals, and even though you may not have been handed a $2 satin ribbon to celebrate reaching your goal, you should still feel good about your efforts and your accomplishments. Maybe you got that difficult right canter lead for the first time, or managed to maintain your form throughout your entire ride. Whatever the goal was, if you reached it or was close, you should be celebrating.
Knowledge and experience. No matter how many times you ride at home, there are certain things you can only learn by going to a horse show. Horses react differently in an unfamiliar setting, and a good rider should be able to manage their horse in any location, not just in the arena they ride in day in and day out. Because of this, horse shows are great places for learning and gaining experience, and learning something new about yourself or your horse is far more valuable than a ribbon.
New friends Horse shows are a great place for socializing and making friends. Where else can you find hundreds or even thousands of people that share the same passion? When you make friends on the show circuit, they will support you through your triumphs and defeats, and many will do so for a lifetime. Friends like that are far more important than any awards; ribbons can't help you when you call on them in tears.
Amazing memories If you compete in horse shows, you will be guaranteed to leave with incredible memories. You will be blessed with many pictures and video of your classes, but you will also have memories that stretch beyond the ring as well:; the time spent setting up and tearing down, grooming and bathing your horse, the warm up, the nerves, the pep talks, the lessons, and the friends and family that were there to see it all. These memories are far more important than ribbons, because unlike ribbons, they will never fade away.
There's nothing wrong with winning ribbons as long as you remember that you can win without them, too.