I agree with helgabb... If you are just going through the motions, in anything, you are being shallow.
It is relatively easy to find out the minimum that you have to do to pass for a normal human being. This is relatively typical, and a good way to be shallow, but not a good way to stand out.
By being yourself you should ideally be seeking that which sets you personally apart from the rest and expressing that.
Definition of "Deep" (opposite of shallow) taken from urbandictionary.com:
“1. Difficult to understand.”
“2. Very intense, profound, or intriguing."
So depending on who you talk to, if you are saying something deep, they will likely react in one of the two above ways.
There may be people who at present are seemingly incapable of being deep. To some it comes naturally, but in many it seems to have been sought out and eliminated during their upbringing which is generally intent on making everyone as similar as possible, at least outwardly.