Yes! I wrote what started as a short story when I was 12, and it evolved into my first real attempt at a novel. Over the next three years I got about 26,000 words in and had a very very loose outline. However, I got stuck and never finished it.
My mom loved it, and kept asking when I was going to finish it. I tried to revive it in college, revamping the plot a little bit and giving the characters a little bit of personality. However, I just couldn't get behind it - it still felt childish and unrealistic.
Fast forward to this February, about 11 years after the initial attempt. I really didn't want to do work one day, so I ended up going back to that story instead and tried to fix the outline. I cut a lot of characters, added some new characters, totally nuked the plotline, and it's barely recognizable now. One of the main characters kept his name, another kept her backstory (the MC), and two secondary characters kept their basis in place. There are one or two scenes that stuck around, but for the most part, it's completely different and is now what it was originally trying to be. I just had to grow up before I could understand that the trauma I was trying to give the MC was PTSD, what a reasonable way for her to stop living on the streets was, and to figure out what ages these characters needed to be (they started off 12, now they're 17/18). They also all got personality transplants, so the one who started as "sports guy" is now "lovable nerd with unusual hobbies who loves trying to solve mysteries, rambles a lot, and gets very excited by the things he likes," etc.
After two and a half days of intense re-outlining, I started writing with the goal to finish by my mom's birthday in mid-April. I'm close to 80,000 words in now, hoping my outline makes it to 100,000, and ultimately plan to try to get it traditionally published (after a ton of revision).
It took an absolute massacre of the original, but the premise is still what it was when I was 12: Homeless girl with the same backstory makes a friend and begins to rejoin society as she works through her past. Except this time, it makes sense and is realistic.