I am hiring for a number of sales positions right now and the big temptation is to compromise - you need X hires by Y date and it's tempting to chuck away all those visions of only accepting the best of the best and instead settle for "they could end up being good with an equal dose of training and prayer." It's great that I read Seth Godin's blog this afternoon as it gave me a well needed jolt of reality.
Seth urges marketers "to refuse to market mediocre stuff if that's the best the folks in R&D and production can bring you. The first time, they'll be shocked. Your job will be at risk. But then you'll notice something... the stuff gets better. Fast. In Japanese car factories, this is called kanban. You trade production efficiencies for quality. If a part isn't perfect, the worker refuses to install it. And the entire assembly line stops. Detroit was horrified by this idea. Keeping the assembly line going is the holy grail. Guess what? The line doesn't get stopped very often. Things get better, fast."
The same principles apply with HR - if the cadidates aren't good enough, I will press for more and more and more until I get the ones that meet my needs.