In this instance, cutting corners is equivalent to not gathering data, and acting on the premise that what you want to be true is true. Which is another way of

In this instance, cutting corners is equivalent to not gathering data, and acting on the premise that what you want to be true is true. Which is another way of saying: when there are massive consequences, is not the time to proceed on wishful thinking. Because, as TFA pointed out: if you give people an ineffective vaccine, they will act as though they have an effective vaccine, and likely increase spread. If you give someone a vaccine that has more antibody-mediated enhancement than protective effect (or at least, just a significant proportion of), you may do more harm than good as well. And once you've deployed the vaccine to the general population, you've significantly impaired your ability to resolve questions about the above. When stakes matter, and consequences are large and long-lasting, isn't the time to make blind leaps of faith.