Why do some physical theatre practitioners work with physical objectives?

Physical theatre pieces without objectives can leave the audience feeling unsatisfied, thinking "what was the point." Physical objectives can give a piece meaning and a purpose, things as simple as facial expressions can give the audience a much deeper meaningful, experience. Things like pace, whether movements are soft or controlled can connote so many different things. There are countless opportunities. This all gives the piece purpose and gives the audience a satisfying feeling. Giving the piece a narrative, gives it a sense of direction, where as a series of lifts may make the audience feel as if they are going round in circles.