Why most of the humans are kind-less?
By this, do you mean, "why do most humans lack kindness?"
If so, you beg the question of whether the proposition that most humans DO lack kindness is true or not. In order to determine the answer to this question, you would have to first come up with an operational definition of kindness. How does one define "kindness?"
Once you have decided what you mean by "kindness", you must then randomly sample the populations of humans, representing all ages, genders, cultures, nationalities, sexual orientations and such, and test them for the existence of kindness.
Once you determine whether or not humans lack kindness, then and only then can you begin to determine the answer to *why* it is or is not so.