Differing HP between chars, 3 chars, exactly the same, diff hp/mp.

So, I recently did a little test. Made 3 characters, all thieves, all level 10, all have 4/4 str/int, and 25 dex with 37 luk(at level 10). None have hp/mp raising equipment. None have bought any NX items. Both are brand new characters. Except they have different HP/MP.

So, I strip them down of equip just in case. These are the results:

Character 1
Hp: 322
Mp: 132

Character 2
Hp: 299
Mp: 138
(Sadly, this was the character[for it's name] that I was going to stick with. )

Character 3
Hp: 310
Mp: 148

At first, I thought maybe It was because I skipped the very first beginner quests for char 2(kill the yeti jr's, whats for dinner), and those, for some reason, gave extra hp/mp. But character 3 did all the quests and he was different too.

So why the leeway? And, come to think of it, where does the difference begin? With the Dark Lord extra hp/mp?(probably. But why?)

Note: Sorry if this/the answer is common knowledge. Gotta start somewhere. http://forums.mapletip.com/index.php?showtopic=111995