Stepper Motor Spinning Slow

But I would want to understand why the code below doesn't work?It is expected to do same think but not.

var step = 0;
var steps = [0b0001,0b0011,0b0010,0b0110,0b0100,0b1100,0b1000,0b1001];
var stepperPins = [D1,D2,D3,D4]; // Change these to pins for your motor driver

function doStep() {
 step++;
 digitalWrite(stepperPins, steps[step % steps.length]);
}
var stepInterval = setInterval(doStep, 1);