Maxing out isn't necessarily a good indicator of overall strength....so what you can lift 350lbs...for one rep...

When it comes down to it, the best indicator of strength is the combination of muscular strength and muscular endurance.

Example: It is overall better for you and more effective if you bench press 250lbs for 8 repetitions than if you are doing 300lbs for one repetition.

In a real-world situation you will more often than not be called to action using your muscular endurance in combination with your muscular strength, and not just asked to lift something really heavy, one time.

::end rant::

edit: also as an example above (one i have personally experienced) maxing out with weight is one of the most common causes of injury during weight lifting (right below incorrect use of weights) I also had a nagging shoulder injury that was caused by maxing out for bench press, hence the reason I have done my fair share of research and had discussions with many professionals on the use of max weight vs. rep weight (it is no coincidence that my shoulder is now not only fully healed, but much stronger than it ever was when i was maxing out)