We have opened the lid too much. Everyone does it. The problem is not curiosity; the problem is losing heat, slowing the cook, and making the smoker work harder every time you peek.
We have wrapped too early because the clock made us impatient. The result is usually softer bark and a cook that tastes fine but does not have the texture you wanted. Bark should guide the wrap more than time alone.
We have under-rested meat because everyone was hungry. Resting is not a fancy chef move. It is how juices redistribute, carryover finishes, and tough cuts relax enough to pull or slice well.
We have also learned that a great sear needs serious heat. If the pan, grate, or grill is not hot enough, you are warming the steak instead of building crust.
None of that ruins the hobby. It is the hobby. Backyard BBQ gets better when you notice what happened and write down what you would change.
The only bad BBQ mistake is the one you do not learn from.