Getting into a consistent fitness schedule is essential if you're on a quest to be fit and healthy. I know for my busy life, if I map out what days of the week I plan to work out, it helps me stick to it. While a regular exercise plan is beneficial, you still want to make sure you're mixing up your routine, especially when it comes to strength training.
You may have learned a certain group of exercises, and have gotten into the habit of doing them in the same sequence every time so you don't leave one out. If you're constantly doing your exercises in the same order, your muscles will become efficient at doing them, and you'll be more likely to reach a plateau. You'll get more out of your strength training sessions if you mix your exercises up, because it'll fatigue your muscles in a different order, which will be more challenging. Not only that, but varying your routine will also keep you from getting bored.