The phrase "Like Clockwork" is used so often because a clock has an exact job to do for the extent of it's lifetime. The process unwinds from seconds to minutes, minutes to hours and finally hours into days. It is never interrupted. It is always consistent and it always follows a pattern.
The goal of the clock is to tell the exact time as it is set. In order to arrive at the final goal of changing to the next day, the previous two steps must occur sequentially each and every time. If any of these steps are missed, the time will be off and ultimately, the goal will not be met. No shortcuts are permitted in this consistent day in and out process.
The same holds true for any of the goals that you set to accomplish. Start out with the bigger picture (your day change) and work it backwards into exact steps (minutes, seconds etc.) to find your starting point. The more defined the steps, the higher achievement rate of your goals. Steer clear of cutting corners because as easy as it looks, the clock doesn't magically arrive at tomorrow. It follows other important steps that keep it moving to it's destination. Create a fine tuned process and stay on task whether it is a month, a year or five years. Soon enough your goals will be like clockwork as well, precise enough that you can set your watch to them!