Cycling through some motors

Anyone see anything wrong with this code? I am trying to rotate setting some motors to high/low as a test, but sometimes 3 come on, and it misses other ones. I don’t see what could be wrong with this, but I just want to make sure before I go to the lab tomorrow.

When I tried some other code that shifted through the motors with names for the motors (m1) it would work individually on all of them except for skipping some.

void setup ()
 pinMode(0, OUTPUT);
 digitalWrite(0, LOW);
 pinMode(1, OUTPUT);
 digitalWrite(1, LOW);
 pinMode(2, OUTPUT);
 digitalWrite(2, LOW);
 pinMode(3, OUTPUT);
 digitalWrite(3, LOW);
 pinMode(4, OUTPUT);
 digitalWrite(4, LOW);
 pinMode(5, OUTPUT);
 digitalWrite(5, LOW);

void loop ()
  for(int i = 0; i < 5; i++)
    digitalWrite(i, HIGH);
    digitalWrite(i, LOW);

Beware that digital pins 0 and 1 are also used for serial I/O to the host (via the FTDI chip). But since you're not using Serial.print(), that shouldn't matter.