We say that the 2 percent objective is “symmetric” because the FOMC would be concerned if inflation were running persistently above or below our objective. 2/3  BIS central bankers' speeches  The unemployment rate is low and expected to fall further. Americans who want jobs have a good chance of finding them.
Moreover, wages are growing a little faster than they did a few years ago. That said, they still are not rising as fast as in the years before the crisis. One explanation could be that productivity growth has been low in recent years. On a brighter note, moderate wage growth also tells us that the job market is not causing high inflation.