My mistakes (list always growing):

Too much cheese
pork rinds on induction
legal treats - to many mock danish, etc
Not eating enough veggies
Not following induction STRICTLY
THe "oh, just one bite won't hurt" syndrome
Wanting instant results/feeling like I am failing when I plateau.
NOT being rigorously honest regarding food content (ie, if a dressing at a restaurant has sugar, etc).

My biggest mistake - listening to all the negative hype about Atkins, and leaving this WOL to join WW/low fat eating because my family THINKS they know what is best for me *sigh*.