NB:  This is the way I understand the PhD process.  I'd be keen to hear how others think of the PhD process and what it entails.

One of the more difficult things about the PhD is that in order to actually complete the PhD, and thus the set of skills it represents, you have to put down some of the skills you acquire along the way.  This is most salient for me in the uptake of information.  A PhD candidate in the serious pursuit of their studies at some stage acquires the ability to absorb a ludicrous amount of information.  Now, people in a general way tend to be good at absorbing information, but a PhD is in part a refining of this ability to the point where it happens fast, accurately and all the time. 

The problem arises, however, when one needs to finish the dissertation.  It is that this point that the acquisition of information must be dialled down, as it were, in favour of the creation of information.  Now, most will say "but surely in order to create more information you need to acquire information to begin with." This true, but only to a point.  After all, you can collect almost an infinite amount of information on even the most niche of subjects you can imagine.  The point is that once you are towards the end of the disseration process, the imperative becomes the completion of the work.  However, in order to have reached that piont, you were required to create a particular faculty in yourself, a faculty that can threatens to undermine the very object it was created in aid of.  

This paradox is lovely, as it becomes an exercise in moderation.  It also shows the appropriate mastery of the scholarly mode, in that done correctly, one should be able to acquire information, but in the appropriate times know when to put down this ability and get to the task at hand.  Producing output without seeking to understand that subtlety of the world around you is as problematic as becoming so caught up in the minutiae of life that one is stuck.  One needs to learn when each is appropriate, and commit to each in varying doses in accord with circumstance.