the Garrard 301 plater is concaved.

After noting the comments of the "slightly concave platter"
I proceeded to check my mid run 301 grease bearing 
and low and behold it is slightly concave.

There's always something to learn in this hobby. 

I believe it was made this way intentionally

I don't know if it was intentional, but I would think it's easier to make it flat, certainly if turned on a lathe. A slightly concave platter, used with a clamp, helps flatten the LP. 

The original platter was not turned on a lathe. It was cast and then spun balanced with drilling of the heavier spots. I wish the chassis was also cast-but it was stamped. There is lots of literature available on this. EW Mortimer's book on the history of Garrard is a good start. 

everything I ready prior to my posting said it was a design feature, I was just surprised to find it in a table designed in the 50's.  The old Garrard's were better designed then I originally thought, well at least included some modern thinking. 

My head is gong to explode. Google Art Dudley and Thorens and Garrard and read his essays. Don't believe Art Dudley, google Ken Shindo and Audio Note and Garrard. The Thorens TD124 and Garrard 301 were designed and built with a level of precision and craftsmanship and engineering that remains unmatched to the present day. Both were built to be used in the broadcast industry where it was common to run the decks 24/7 for months at a time. You apparently have a 301 so did you not do any research or listening comparisons before buying? Both do have their minor challenges. The TD124 platter sits low in the chassis and can create challenges getting a modern arm low enough. The Garrards require a plinth that is massive and arguably "tuned" to cancel out motor noise.