I have a question about the function Animation.CrossFade()

Hi everyone .
I have two piece of animation clips ,each of them last 1 second.when i use crossfade function to change the animation like this

GetComponent<Animation>().CrossFade(roll.animation.name);

if(GetComponent<Animation>()[roll.animation.name].normalizedTime > 0.95f){
controller.isRoll = false;
animationState = Run;
}else{
controller.isRoll = true;
}


this charactor will roll forever.when i change that into

GetComponent<Animation>().CrossFade(roll.animation.name,0.05f);

if(GetComponent<Animation>()[roll.animation.name].normalizedTime > 0.95f){
controller.isRoll = false;
animationState = Run;
}else{
controller.isRoll = true;
}


It works well .
Can anyone tell me the reason? THX.

 

-_-