When I was racing in the late 80s and early 90s, I stopped having fun. It became a chore. Looking back, I probably was overtrained, and certainly was training wrong for me. The season where I got injured halfway through the previous season and when healthy decided to start training in august for next year finally did me in. By the next May I hated riding. The last ride was a beautiful summer day up the mountains. I got up there and said "I hate this ****. It's stupid. I am going home".
I quit riding and took up motorcycle racing and chasing goth girls.
I took up riding again when I was 40. At first I was just riding for fun and to get into shape as I was fat and pathetic. I wouldn't even use a bike computer and swore that I'd never race again. After a while I decided that maybe a half century would be a good goal. It was so hard! My friend had to tow me the last 20 miles. Then I got in a bit better shape and tried some centuries. That got easier so I did the Death Ride. I'd never gotten around to it when I was racing. The first time was the hardest thing I'd done. It was so miserable and I swore I'd never do it again. Two weeks later I was planning for next year. A couple years later the Death Ride was no longer enough of a challenge. I heard about this two day race called the Everest Challenge. 29,035 feet of climbing in two days. I figured that if I was going to do that I'd better learn how to ride in groups again, so I started doing racer group rides with lots of climbing.
My new friends on the group ride suggested that I should get a license rather than riding in the public category. I did EC as a cat 5, couldn't finish, but that made me determined to train harder and finish the next year. Part of that training would be to do normal races. So it took about six years but I am back to racing again. Since then I've finished EC three times and placed as high as 12th in the 45+ field and gotten some top 10s in other races. There is a large gulf between me and the good guys, but it's fun to see how well I can do with what I have.
This time I am less dumb about training and rest, and I am only doing the races I like instead of trying every race on the calendar.