I'm amazed at the break throughs that people can realize. There are a few folks I run with every few months. One month they will be on par or slower than I am in a track workout. A few months later, I see their back slowly stretch away from me.
At first it's frustrating and baffling. I haven't been lolly gagging, I've been running and staying healthy. So how could they improve so much, so quickly?
Only after speaking with them do things become clear. They haven't run some momentous workout which imbued them with the ability to run like the wind. No -- instead they've simply been running consistently, and at a higher mileage. 60 miles per week, with a few quality workouts a week, coupled with no injuries does amazing things for the amateur runner.
Consistency in training is the single most important thing that leads to success. That consistency comes from concentrating on the task at hand - neither dwelling on the past nor looking too far forward. The only thing you can control is the present, and when you focus on that and remain consistent in your training, you'll find your greatest success. Daniels' Running Formula-3rd Edition
Above all else, it's important to remember that no single run will make you, although it may break you. The only method of filling a bucket of water with an eye dropper is a single drop at a time. You can't speed the process up much. You can grind it to a halt and often even put a hole in your bucket.