It's not just impractical. It's a complete nonstarter in any competitive job market (like the bay area).
First, contract to hire is a pure negative for the employee. People can "try a company" out just fine with a full time offer and then quit if it's not a good fit.
Second, it's far easier to find good people by poaching from other companies than it is by traditional means. No one is going to quit their job for a 3 week contract even if they're really unhappy at their current job. So, with this approach, you've just removed the biggest pool of talented prospects there is.
First, contract to hire is a pure negative for the employee. People can "try a company" out just fine with a full time offer and then quit if it's not a good fit.
Second, it's far easier to find good people by poaching from other companies than it is by traditional means. No one is going to quit their job for a 3 week contract even if they're really unhappy at their current job. So, with this approach, you've just removed the biggest pool of talented prospects there is.