I have a loop but always inputs the same condition, please see the picture.
You have the motor power set to 1 and you are waiting for 1 full rotation. If the motor moves at all, it will take a long time to complete one rotation. Most of the loop is spent waiting for the rotation to complete (or if the motor is not moving at all, then the loop never actually loops).
Try using a higher power - at least 10. Also, use less than one rotation, or use time (just a fraction of a second) instead for the duration of the motor block.