the DC seems to be completely random for every enemy, and when I pick the same enemy more than once, it stays the same every time

the wiki isn't so informative about how pick pocket works; I've only gotten it to work once, and I don't know how I did it
GMK says it always works on an enemy if I use it right when I kill them... and apparently, hes right; in that case, the DC is reduced to 1, so I assume that it does work on corpses, although the wiki says otherwise
the DC seems to range from anywhere between 0 or 120 more often being 0 or 120 than a 1d120 die roll should be
it also does not work on players, even if their DC is 0
a player has a set pick pocket DC when they log in, and it only changes if they relog; I tried having a player re-zone, with no DC change
so, how does pick pocket work? is this working as intended?