Having more embryos to choose from is great, but the best embryo of 1000 or even 10 isn’t likely to be chosen for implantation if your predictor isn’t very good.
Choosing ‘the best’ is irrelevant and a distraction in most contexts. It is not the case that you will be ‘likely’ to choose ‘the best’ if you have a ‘good’ predictor—because for any ‘good’ predictor, no matter how good it is, the probability of ‘choosing the best’ still becomes arbitrarily close to zero as n increases (specifically, it goes to 1/n). Nor does it particularly matter if you do select the #1, by chance, because you still have high odds of not yielding a downstream success like a live birth.
(Of course, the expected gain—which is what matters—just keeps going up and up with n...)
Choosing ‘the best’ is irrelevant and a distraction in most contexts. It is not the case that you will be ‘likely’ to choose ‘the best’ if you have a ‘good’ predictor—because for any ‘good’ predictor, no matter how good it is, the probability of ‘choosing the best’ still becomes arbitrarily close to zero as n increases (specifically, it goes to 1/n). Nor does it particularly matter if you do select the #1, by chance, because you still have high odds of not yielding a downstream success like a live birth.
(Of course, the expected gain—which is what matters—just keeps going up and up with n...)