The number 3 symbolizes the generative force, creative power, multiplicity, and forward movement.  They are about planning and preparing, putting the details into place before beginning the work.  Pentacles are associated with the material world, acquisitions of wealth and possessions, our connection to Earth and Nature, sensation, matters pertaining to the physical plane, the body, health and physical or sexual activities.  Pentacles can also be connected with practicality, groundedness and being realistic.  The 3 of Pentacles represent sharpening professional ability; successful effort using creative and practical skills; and new undertakings that bring material rewards.

Looking at these two cards I was struck by something - in both images there is one person directing the action and one actually doing it.  On the Mitologico 3 of Pentacles we see Circe (at least I think it's Circe) sending Odysseus on some task.  I don't remember the specifics but my guess would be that in order to gain his freedom, she requires him to do something for her.  He will learn to master the task but it does not seem to be one he will enjoy.

On the Fantastic Menagerie 3 of Pentacles we see two well-dressed creatures standing near the jobsite chatting while behind them we see a third creature carrying something on his head.  Looking at it I thought the bird might be the master, the one who is paying for the job.  The mouse (?) in the brown coat may be the architect and the laborer is the one who gets to actually carry out their plans. 

Both these cards are a reminder that sometimes our creative energy and ability to manifest that energy is driven by someone else.  Perhaps we let someone else guide our vision.  Or perhaps one of the concept portrayed by this card  is that of manifesting someone else's vision before we are able to manifest our own.  I have often seen this card described as the "apprentice" card.  Maybe we need to be apprentices because we have to learn the ropes and start from the bottom even when it comes to our own creative endeavors.

I find it interesting that young people entering the workplace (myself included) often pooh-pooh the idea of needing to "pay their dues".  They believe that they have brilliant ideas and should be able to change everything as they see fit.  They don't value the idea of putting in some time to check out the lay of the land; to see how things currently work at a new job.  They believe that education and skill should outweigh experience and knowledge.  The reality is that a balance of the two is necessary in order to be able to fully express one's own creative abilities.  Education and skill are only the starting point.  In order to learn how to fully hone these abilities and put them to work in an effective and rewarding way, we need experience and the knowledge it brings.  In some respects I get the sense that this card is a reminder that sometimes (no matter how much it might hurt the ego) it is necessary to humble oneself to the master in order to truly acquire the training and experience necessary to achieve our own personal success.