If it was important, more airlines would ask for your grades in their application processes - few bother. Overall grades and numbers of attempts has had absolutely no correlation to the success or otherwise of the guys from my course, and that was in 2002 when there were more newbies than you could shake a stick at, and airlines went wild with their arbitrary requirements for the few jobs available.
That's not to say that you shouldn't make the effort - the discipline of studying is good for you - but don't get hung up on the outcome as long as you bag all 14. Flying grades and your ability to pay your way through your post-graduate training are way more important than your groundschool.