Among the list of top-class mares who, for one reason and another, failed to reproduce anything like themselves are some of the very best racehorses of the past 30 or 40 years.
Genuine Risk, as a couple of readers pointed out, never had a winner. Champion Gallant Bloom had only a couple of winners. Genuine Risk’s arch-competitor, Bold n Determined, had a poor record at stud.
At a less-determinedly negative level, Meadow Star had a record similar to that of Winning Colors, with stakes-placed horses but not a stakes winner.
Anyway, the point of this exercise is not to say that any of these mares were “bad.” They were not. Genuine Risk, for instance, got in foal easily but did not carry the pregnancies to birth, with few exceptions. Gallant Bloom started off well enough reproductively, then went barren for years.
These are not the records of horses who could not produce good racehorses. They simply did not produce many foals at all.
If we look at the records of mares, especially through the lens of those who expect a mare to produce her best offspring in her first four or five foals, it’s amazing that any of them succeed. It’s almost like playing the lottery, and in that regard, Thoroughbred reproduction is a gigantic game of chance.
In comparison to top-class stallions, who nowadays regularly sire a hundred or more foals in each crop, mares have severely limited opportunity to get top racehorses. For many, it seems, by the time the breeder figures out what matches the mare best, she is too old to take advantage of it. [Somethingroyal, of course, might disagree with this statement, having foaled Secretariat when she was 18, as memory serves.]