While researching this card a few days ago, I came across this site that compared the 3 of Pentacles from several decks. I found it useful and I hope it'll help you with this card too.
http://supertarot.co.uk/disk/threed.php
I personally see the 3 of Pentacles as an indication that the person has the skills necessary to get the job done. As a challenge card, perhaps the person is has not yet reached the optimum level required to excel in his work; he/she needs time to familiarize him/herself with the tasks required of him and the people he/she needs to work with.
Being a number 3, it means there is still work to be done before this person
is recognized as a true master craftsman. At this stage, he/she is recognized as having the necessary skills but his/her ability has not been proven (beyond reasonable doubt) on track record within the organization. Retroactively apeaking, of course, there are too many probabilities.
This person may be holding the same job with new changes to the work requirements (a promotion with more responsibilities or an inter-dept transfer with different responsibilities); in a new organization learning the idiosyncratic temprement of the company; on probation for various reasons... the list goes on and on...
The gist of it is that the person needs to put in effort to be recognized amongst his contemporaries; it won't be handed to him/her on a silver platter. My interpretation is based on the card appearing in the position of the spread mind you mentioned earlier, not the all-encompassing meaning of the 3 of Pentacles card.
The site I provided gives a comparison of the 3 of Pentacles from several decks so I think the deck you used for the reading may have a slight variation to the interpretation I gave. Hope it helped anyways.
Ash