How many coaches have taken kids from close to the beginning and brought the bulk of them through a medium-long senior career in the post-figures era where there wasn't a centralized force making coaching decisions, like in the Soviet Union and in China? That is the exception: even Tutberidze, who focuses on younger skaters than most, coaches kids who come with their triples, some trained by her team, but many from across Russia Carlo Fassi took ready-made skaters. Frank Carroll's only skater to win an Olympic gold medal came to his team -- Congemi was Lysacek's main coach while Goebel was still competing -- as a two-time Jr. World medalist and a competitor at JGP/JGPF.
Of the major coaches, Mishin may be the unicorn.
Many skaters attribute their superb basics, whether skating skills or jump technique, to their early coaches: Berezhnaia lauded her childhood coach for her skating skills, not Moskvina, Virtue/Moir got theirs under Paul McIntosh, etc. I think that not having to undo incorrect technique is an often unacknowledged advantage.
Also when a skater is going through a physical transition, whether having body changes, or bone-growth conditions, or recovering from a major injury or illness, or making a coaching change and uprooting, sometimes geographically, even if a net positive, holding water can be an admirable achievement.