Meditation is easier than you think (3)
Myths of meditation
Myth 3: “If my mind wanders during meditation, I am doing something wrong.”

Minds wander. That's what they do. So you are definitely not doing something wrong when you notice your mind has wandered. In fact, when you notice your mind has wandered, you are actually in the process of doing a great job with your meditation. Noticing your mind has wandered and then bringing it back to your anchor, is the whole business of meditation. And the more times you notice it has wandered and then bring it back to your anchor, the more you are into the practice of meditation.
Think of it this way; let's say you decide to get fit and to do so you start to do arm exercises for your biceps. Sure, you will get some benefit from just hanging on a bar, like in those bent-arm hangs they always made people do in gym class. But you know, and I know, that the going up and down when we do pull-ups, is actually a little harder and builds the muscle more quickly than sitting in a bent-arm hang. If you are doing the repetition of pull-ups, or the “reps” of weight lifting, the power of the exercise comes about in the movement of the weight, not just holding the weight.
So our practice of meditation needs some “reps”. It needs to have the exercise of catching our self in noticing that our mind has wandered, and bringing it back to the anchor. The more reps-the more you are practicing.
When we are meditating, we are both asking our mind to not wander and know it will wander anyway.
Additional Resources: Meditation for Beginners. Techniques for Awareness, Mindfulness, and Relaxation. By Stephanie Clement.