First place gets a Cadillac, second place gets steak knives, the rest get fired? (a quote from Glengarry Glen Ross)
That's a BIT of an overstatement depending upon the particulars. Outside sales for complex products can require a quarter or two ramp-up so you want to be somewhat selective. If you're hiring someone for that sort of position though they probably have some sort of track record.
For an inside sales position, you're not all that far off though.
As I've seen it put in another discussion, "sales managers don't have any trouble firing people."
If you need 2 sales guys, hire 3, give them a month and fire the worst one.
That is horrifying to me as a developer, but apparently this is fairly standard for sales.