[Linny]

They had run in the UAE Derby and Guineas. Those races can be tough (like this year, Cocoa Beach was 3rd in the Derby) and they are also not placed that well on the calendar.
Horse that ran well in either of the two have flopped in KY and those that ran poorly behind top class Southern Hemisphere colts and fillies (Asiatic Boy last year) have even less shot. They don't usually make it at all.
The other option is essentially "allowance" races for horses classified at up to 110lbs, which they run often at the Carnival. The problem is that those races are too easy. They don't get you ready for KY either. Meanwhile the best US colts are training hard and facing off in Florida, Cali, Louisiana and even NY.
The point is that yes, they have had success in Europe in the spring, but not THAT much and not with Dubai based horses. Again I say "that much" because they own much of the best bloodstock on earth. Also, if they have done well there, not here you have to look at the differences between the two places (US vs Europe) and try to find reasons.