"else if" requirement met but not working, why?

Works totally fine when I try to enter (1) or (2). But when try to enter(3), the statement just being skipped. Why?

if (fla == 1) {
  for (weight = 0; weight < 50; weight = weight) {
    System.out.println("Please enter weight for single flavour (must atleast 50grams): ");
    weight = in .nextDouble();
  }
} else if (fla == 2) {
  for (weight2 = 0; weight2 < 80; weight2 = weight2) {
    System.out.println("Please enter weight for double flavour (must atleast 80 grams ): ");
    weight2 = in .nextDouble();
  }
} else if (fla == 3) {
  for (weight3 = 100; weight3 < 100; weight3 = weight3) {
    System.out.println("Please enter weight for triple flavour (must atleast 100 grams ): ");
    weight3 = in .nextDouble();
  }
}