The whole point of many of these grants is to invest in research on the leading edge where, by definition, nobody knows whether what they're trying to do is going to work, because it's actually new.

Of course that can be gamed, and of course we need good faith oversight, but if none of the research projects we're funding were to ever fail, that would be evidence that we're being massively too conservative in the avenues for new discoveries that we're investing in exploring.