The way to stabilize

Development Team
1

Hello,

I am new on these forum so hello everybody. I am interested in ArduCopter.

I just start the developper guide on this page :
http://ardupilot.org/dev/docs/apmcopter-code-overview.html

I saw that the loop is made like this
fight_mode–>stabilize_mode–>Rate_Mode

But in the code the stabilisation is made like this:
Rate_mode(low level) -->fight_mode–>stabilize_mode

Why the loop is made like this?

Can someone help me about this?

Best regard.