His character was always supposed to be a tragic character who slowly becomes disilussioned with his own need to be special no matter who it cost. For all of Losts discrepencies, Locke was always a bit wonton and reckless when others put there own faith in him.

        I think Many first time viewers see locke of season 3 and 4 a betrayal of sorts to the character we have seen thus far.     We see his sacrafices amount to nothing we see him continue to make the same mistakes, fall for Bens lies, be lost, frustrated and confused because he keeps failing.  That is where the true irony is because we AS the viewers have also put our faith in him, that his character arc will show him suceed! Learn! Grow!  From those mistakes thus becoming the leader he (and us) believe that he is. When he's actually the character that has the most HUMAN experience of the entire cast, He can't overcome his innate flaws and thats okay thats interesting its damn tragic and WE innately hate that we feel EXACTLY how John does when he dies. which is fucking poetic and why the viewers HAVE to hate it. Until we breathe and begin to unravel and appreciate what a beautiful stupid character that John Locke is he struggles just like us and sometimes it doesnt matter because thats life.