Even though there's been an increased interest in the field from many young (and less young) people for many years, the fact remains that this also came with a steep increase in demand for those same people.
Once you get candidates in front of you, you have to assess whether they are worth your time or if you should move on to a _possibly_ better (or worse) candidates. Unfortunately, you sometime (read: most of the time) do not have the luxury of time before taking that "leap of faith" on someone due to the speed at which developers get picked up.
Some people will say that they can easily filter the good from the bad from spending a few hours with someone, I still find that there is a substantial portion of uncertainty when moving forward with a hire unless you have an overwhelming number of candidates applying and can afford to "try out" quite a few of them.
I try to stay realistic when selecting candidate and aim for the good ones, the ones that will get the job done. Every once in a while, you'll get lucky and find a great one.
Anyway, YMMV.
PS: Depending on where you are located and the type of business you are in, you also need to factor in the fact that you are battling out for the same talent with high profile or well funded companies in your area.