One thing I like about mountain biking vs road biking is, mountain biking requires that you pay attention to the trail, even the easy segments, that way you forget your problems cause the trail won't allow you to think about anything else.
So I went to one of the local single track trails, getting back into it now that spring is here, and was having a pretty good ride. I was flowing through the hairpin turns that cause me headaches on this trail like they were straight. What a great way to start the season. So my mind wandered to what a great post it would make how great this ride was, then I see a large root sticking out in the upcoming trail. It's about 5" in diameter, sticking up like a log and running parallel and pulling slightly to the left. So instead of turning into it and hit it perpendicular or pull up the front and jump it, I'm still thinking about the great thread I'm gonna have. So I just hit the root with the side of my tire and hoped the knobbies grab it. You already know what happened, the tire hit it, turned left, the bike went left and I went right. All this on an easy section of an intermediate level trail. Results were one bruised knee, a cut up shin and one badly humiliated ego.
OK, So I've had my annual reminder, When on a trail, pay attention to the trail.