Usually in a DUI case the officer documents what you did wrong, not what you did right. For instance, the officer's report may indicate you were weaving. However, officers usually don't document proper driving behavior such as following the speed limit, that you were a proper distance from other vehicles, and you obeyed all traffic signs.
There may be other factors to mitigate the effect of any mistakes on the road, such as: road condition (i.e. lack of lighting, road construction, adverse weather conditions, traffic congestion), confusing road signs, you're unfamiliarity with the area, and mechanical difficulties with your vehicle.
In addition, if the officer did not have a valid legal reason to stop your vehicle the court may exclude all evidence against you, including breath tests results and the officer's opinion and observations. Fighting a Search and Seizure violation by the officer requires a competent attorney with the facts on your side, and could ultimately result in the dismissal of your charge.