When I was young, writing was just for fun. There was no worrying about grammar or punctuation, I just wrote. As an adult, writing is so much harder. In order to be published you have to worry about silly things like grammar and punctuation. And your story has to capture readers and keep them reading. Also if you want more than a couple readers your book has to hit the market at the right time. Too much work for me. Is it too late to quit? Yup.