If you place an object and it doesn't show up in your view (like floor plan, elevation, or RCP) and you think it should, you should first be checking the workplane and any offsets (found in the properties of the selected object). If it doesn't show up and you think you should be seeing it, check those options before putting it. If you are clicking, the object is being placed somewhere!
Here is a situation recently run across. If you are having trouble identifying the pieces of the picture, these are shelving units, except they are located above the ceiling plane. When placed, the offsets of these objects weren't paid close attention to so they ended up above the ceiling plane, thus not showing up in any plans, rcp's or elevations. The objects were placed a second time in the correct location (sometimes) but the original objects were left in place. Other elevation views there is much confusion about where the objects are because the modeler 'knows they put them in'.
This results in the double counting of objects, unless they intersect any other elements (which usually they don't) they won't show up in any clash reports or anything else, the only way you would know is if you looked in 3D above the ceiling.
The solution we should all take away from this experience is to pay attention when placing objects to their offset parameters, and if it doesn't show up like you think it should, then something probably went wrong. Do yourself a favor, 'ctrl-z' and figure it out!
