Why does IVF fail with good embryos?

IVF can sometimes fail even with good embryos. The reason cannot be pointed out. Even when every step of IVF goes perfectly, there is still a chance that the embryos fail to thrive after implantation. While devastating, this is always a risk. Despite the best efforts and practices on the part of the fertility experts, scientists and the couple, a potentially promising embryo can also fail to grow.