I think he's asking why the leveling speed isn't equal throughout the whole game. In the previous TES you needed to improve your skills 10 times to level up regardless of your character's overall level - in Skyrim it's not so simple.
Every time you level up a skill, you also gain experience toward a character level up. However, leveling up low-level skills offers only a low amount of character XP toward your next level, while leveling up high-level skills offers more. The required amount of character XP needed to gain a character level up increases with your character level - you usually level up very fast at the beginning, then it slows down.
There are 18 skills starting out at 15, subtract racial bonuses and you get 1495 skill level ups across 80 levels. The average is 18.7 skills needed to advance overall level by 1. At least that's what the math says... I never paid attention to how many skills I had to level up.
how does make skill level points up save many points when does level
Say what?
