Having high hitpoints is good for staying on the hit list, getting people off the hitlist and not having to heal every 3 seconds in gang wars.
It means that for you to attack this player enough to kill him, he will attack you back, and do more damage to you than you have health. So for example, if the hitlisted player has 1k health and you have 100, it might take you 15 hits to kill him/her. In those 15 hits, the hitlisted player retaliates (just like regular hits, where you also lose some hp) and does 250 damage to you in return. Since you only have 100, you cannot take that player on without dying yourself.
Question#1: what is the purpose of having large health points?..i think if you have high health points but you are weak, they farmed you everyday.
Question#2: whats the meaning of this "You dont have enough max-health to take on "player's name" at this time!" ,sometimes when im trying to get a bounty . what is that?.