Starting Strength is another excellent program to follow and if you pick up the book it features an exhaustive description of the bio-mechanics involved in each lift (which you can skip if you just want the charts).
Probably because you weren't focused. For me 1-5's are great - long enough to really build character, but short enough you can have the laser focus that the lifts require. If I'm doing 10 reps 3-8 I'm half there.
The only lift that requires backup (assuming you don't have the appropriate equipment) is the bench press - all others you drop the weight and walk away.