Swimming in or lying beside a pool is the ultimate wish-fulfillment dream for many people. The rest and relaxation of sunning outside is a wonderful invitation. However, depending on who is in the pool, you may be missing out somewhere in waking life.
Evaluating this message depends on who is in the pool and what they have in common with people in your waking life. Perhaps you need to be less of a watcher and more of a joiner.
Do you feel as though you should be "part of the action" instead of on the side, sunning yourself?
If the water seems somewhat unwelcoming, there may be underlying feelings that the pool represents something you are being lured into against your will. In this case, the occupants of the pool may be people whom you generally trust, but also have some misgivings about.