I have learned recently that its very important to match tactics with your goals, or you may end up spinning your wheels and getting nowhere. First a bit of background:
I frequently bike to work for a variety of reasons. Mostly because its fun, and one of the few ways I enjoy getting exercise. My company also has a program where they donate money to a charity of my choice when I "self power commute", which biking qualifies for (I am up to >$150 for the year so far - not bad for something I would do anyway), so there is an incentive there as well. I am also lazy by nature, so when I set my Q2 goals at work (See: Goal Setting At Google for more info on how we set our goals), I added a personal goal to log 350 miles by biking or walking.
So most days (weather permitting), I biked to work, and since I am a GPS geek, I kept track of distance traveled, travel time, and speed (both average and maximum) using a GPS unit mounted to my bike. Notice that I keep track of distance, time, and speed, but my goal only deals with distance. This is where I went astray.
I started to focus on my speed more than distance, and I started pushing myself harder and harder to get faster average speeds. As a result I pushed myself to my absolute limits (which granted is not that hard to do) and I wore out my legs faster, and as a result couldn't bike every day. My legs simply couldn't take it. The end result is that I was not putting miles on my bike, and my goals started to slip. I also wasn't having as much fun.
To fix this I have simply stopped using my GPS on routes where I know the distances already, and stopped keeping track of the time. I have found that I enjoy it a lot more, and I am not killing my legs every time I get on the bike.
The life lesson I learned here is that it is very important to align short term tactics with long term goals. It can be very easy to hinder the ability to reach your goals by taking the wrong path along the way.
Another tangential lesson is be careful of the metrics you use to determine your actions. I only really care about distance, but the metric I followed the most was speed. This caused me to make bad decisions. The metrics being followed need to lead towards hitting the goals. Either the metrics or the goal has to change if one is to see success.
I am not saying one should never explore the alternate path, or try new things. I firmly believe that exploration and risk taking is an important part of growth both as a species and as an individual. However when the goals are set, and you have no intention of changing them, you need to be careful to make sure the steps you take don't lead you to a place where the goal becomes impossible.
Important life lesson there. Glad I learned it.