Rejections are part of a writer's life and, no matter how nicely they're couched, they hurt.
This one began with a list of the things the editor really enjoyed before it reached the stumbling block about motor cycle racing and the hero's motivation to ride the "Widowmaker", a bike with a radical suspension and a habit of killing its riders. She knew very little about the sport, as would most of the targeted readers, and found my descriptions confusing and his motivation unbelievable.
This highlights the difficulty of describing something you know very well to a group who are likely to know nothing. From my perspective, I verged on over-explaining.
The hero's motivation is a more vexing question. Is it my familiarity with the sport and the people who follow it that makes it believable to me? Or is there a more basic problem?
I reread the manuscript yesterday pondering those questions and am still no closer to the answers.