Consistently building new habits can lead to personal breakthroughs that wouldn't have otherwise happened.
Here's a personal example: I've been really working on my fitness consistency over the past 6 months. I've also set a goal to improve my tennis strokes. Last night I played tennis with a friend in 90+ degree heat and lost the set we played (it wasn't even that close). Afterwards, we continued to hit for another 20 minutes or so. Instead of being down mentally and exhausted physically from the heat, I still had a bounce in my step from the improved fitness. Also, I concentrated on improving my strokes and wanted to get better. After about 10 minutes, I had a breakthrough in the development of my strokes and my friend immediately noticed I was hitting much better. Now, I'm even more excited about getting out and playing more. If it hadn't been for consistently achieving smaller goals, I probably wouldn't have had this breakthrough.
These same principles can work for you in all areas of your personal and professional life. Consistency is the key!