Can problems in the colon develop over 2 years or go undetected in a colonoscopy? had colonoscopies yearly from 2018-2021, all of which were clear, usually have constipation problems, but 1 recent episode of watery orange diarrhea has me worried?

There are no guarantees that a polyp or a colon cancer couldn't develop since your colonoscopy, but in my experience an occasional episode of diarrhea is rarely caused by colon cancer or a polyp. I would be more concerned if you passed black, mahogany or frankly bloody stools. I expect that your gastroenterologist will reassure you. Orange diarrhea is not considered bloody& should be transient

It is notlikely that anything was missed on three successive colonoscopies, but it is possible to develop new problems of the colon since that time. It also could be not related to the colon at all. If your bowel movements have changed, increase your fiber, increase your fluid intake, and if this does not help, see your primary doctor or your G.I. doctor. Good luck.