There can not be a deficiency of being, but there can be a felt deficiency of being. This seems to be a misalignment of experiencing which deflects the sense of being out of centre. If you keep trying to regain your seat you as often keep sliding off it. What is constant of the falling, a kind of parallax, a stationary motion. It's impossible to think your way back, it is a disconnection of will and knowing. It reminds you of your helplessness by your being helpless.