Believe the part you're referring to is the stem. Anyway, thanks for the photo which clears things up.
Some of the manufacturers are clear that their equipment can fatigue and fail, and that these failures are considered normal and not covered by the warranty. I've seen a couple of owner's manuals that mention this, and advice the rider to stop riding and have the bike inspected immediately if any movement, looseness or creaking noise is detected. It's really up to the rider then to inspect and monitor his own equipment.
Setting an "expected life" seems like a good idea, but anything they put out would have to be wildly conservative due to the wide differences in loads and stresses each individual puts on their equipment. If they told us to replace the frame or fork at a fixed interval of time or mileage to preclude fatigue failures, I doubt few would do that anyway. A better plan would be to make sure the part is designed so that any fatigue crack can be detected in plenty of time before failure. And then to educate the users as to their responsibility to inspect and monitor before any total failure occurs.
Anyway, hope you have a much better experience with the Cervelo and that you ride it in good health for a long time!