you paint the circles one over another, same center, size changes

try i-=3 in the for loop line + noFill

1.     for (float i = 10; i > 0; i-=3) {
2.        noFill();
3.        stroke(244,2,2);
   

This recent post covered something very similar...

It didn't work because you weren't scaling your alpha values correctly...

Firstly, you were dividing the increment by ten, yielding values between 0.1 and 1. Unless life was 255, that wouldn't have worked, even in theory...

Also, you were layering the shapes on top of each other. Your second piece of code works because you have a fixed alpha with layering of the shapes, and you are dividing 255 by the correct number.

Lastly, I'm not sure if you meant it this way, but your snappy responses aren't very polite... we're trying to help you.