At first, it doesn't always feel like that! Much of early taiji play brings a realization of how uncoordinated and disconnected we are! (I should say "I" rather than "we," as this was my own experience. I suspect it is also the experience of others.) It doesn't feel "deep" nor spiritual, but merely clumsy. Yet, from the very beginning it is clear that there is something quite good in this body consciousness practice. At the very least amidst the clumsiness is a profound relaxation. After practicing a while, physical, mental, emotional, spiritual benefits are quite evident.
A few pointers:
a) I have discovered that before any moving taiji it is very helpful to practice still qigong. Qigong has sitting meditation (much like zen sitting practice), but let me suggest standing giqong. It is quite simple to practice. Assume the wuji opening stance (feet shoulder width apart, knees unlocked, slightly bent, shoulders relaxed, arms to the side fingers pointing downward with a gap at the armpits thus keeping the arms a few inches away from the body, head as if suspended from above a by a cord—the whole stance is rooted into the earth.) It takes longer to explain that to apply! Then breath deeply and gently from the abdomen (see belly breathing).
Meditatation in this wuji position for several minutes before you begin to do moving taiji, I have found a wonderful difference. The stillness of wuji is carried into the yin yang of movement. I am experimenting with other qigong standing positions (there are very many) that free up chi in different ways.
In ancient times most practice was of this still variety. I have discovered that, when time allows, half an hour standing meditation followed by and hour taiji play is very helpful.