People in existing teams will be very fatigued from getting to know new people and then trying to forget them. This is well documented in the military. After a while veterans don't want to get to know the fresh reinforcements that arrive into their unit, as the new guys will probably die quickly simply because they are inexperienced and thrown to battlefield. As a result, any investment in social relationship with them is wasted. And as a result, the whole unit will get grumpy.
We never found smart effective folks who did not want to get to know newer smart and effective folks.
Less than 50% of hires stay: "oh geez, more meat to the grinder."
More than 50% of hires stay: "A new guy came, do you play ping pong?"
But my cut off point might be way off. And there might be some elasticity between those where people are more iffy about the whole deal.
I'd suggest testing this. Stack slightly not so promising new hires to one team and more promising in other. Let's hope there is different retain rate. Now you can measure the performance changes of both teams and see the net effect.
So even though this is implicit elsewhere, we make it explicit (if you don't think we're a fit for you, or we don't think you're a fit for us, we'll part ways)
Let me know if that makes sense
By interviewing and throwing away potential false negatives you also cut down on the number of people failing probation. You can't have it both ways: not interview and keep the same number of people.