Not necessellery!
If you do find, using an accurate test method, that the camera/lens does misfocus in a consistent manner, then you'd be wise to send it in for a calibration check/adjust, making sure that they only adjust the lens at this point. If you have other lenses, and they work perfectly, then if they adjust the camera(mechanically/electronically) then the other lenses then may be out too.
there's a pretty good paragraph or two about misfocusing lenses and how it kind of works in reality.. done by lensrental.com
Have a read of this when you have the time .. it's worth it to understand what and why cameras and lenses misfocus.
In the case of the 80-200/2.8 lens of mine, this(misfocus) happened on every single attempt, unless I used LiveView to focus the lens at those parameters(focal length and focus distance). Otherwise the lens worked flawlessly.
Consistency is the key, if you get misfocus one day, but not on another, and you're locked the tripod down properly and made sure that the camera has been aligned correctly to the test target, and so forth, then I'd keep the gear and not send it in.
if one day, at a later point, you redo the testing and find that you've suddenly noticed that the testing is producing more consistent misofocusing results(you probably have figured out the key to getting consistent results!.. Do them one more time just to be sure, and then send in the gear to be properly calibrated(but before the warranty runs out.
Also note that I forgot to add into the previous text that you have to defocus the lens after every focus acquisition test shot. So focus, expose and then defocus the lens again before the next shot. I think I took about 10 images of this particular session. And when you defocus, do so in both directions, ie. both to infinity and, for the next test exposure to closest focus distance(MFD).