is to levelsit or rank slowly for your benefit of learning the class. It is good to understand your strengths and weaknesses and those of your opponent at all levels.

Say you're a storm shaman and you can hold your own pretty well against most enemies but you find yourself running low on mana. Then you roll a warrior as your next character and there's a giant shaman in your range. You should know, from experience, that he'll have a hard time having enough mana to kill you so you can string the fight out and eventually win.

If you race to hero without testing yourself thoroughly on the way up then you will find your strategies and experience limited.