Question: How does evalf@Int choose points?

Hello people in mapleprimes,

I have a question about how Int does.

The following function spy returns 0, of course, with a side effect of listing the value of x one by one to secrets.

secrets := NULL:

spy:=proc(x::{name,numeric})
  global secrets;
  if type(x,name) then
    return 'procname'(args)
  else
  secrets:=x,secrets;
  return 0;
  end if;
end proc;

And, with this function, calculation of the Int, that is, following brings a sequence of numbers:

evalf(Int(spy,0..1));

secrets;

.7506605773, .2493394227, .9118140517, 0.881859483e-1, .9970470440, 0.29529560e-2, 1.0000000000, 2.2449529449*10^(-11), .5000000000

The question I have is why the number of this sequence is not from smaller( or greater) to greater (smaller) in order,

but in random order. And, numerical calculation of Int can be done with only 9 points extracted?

Best wishes.

taro