Jiu Jitsu has 4 basic positions. Mount, guard, back, side. Then from these there is open guard, butterfly guard, 1/2 guard, spider guard etc. Then you can get more esoteric and break it down further and into more specialized positions like 50/50 guard, turtle guard, upside down guard, 1/4 guard, DeLaRiva guard, etc. Some of these positions are controlled points in a transition...where if there was no control, it would be a transtion or a scramble.
You can find opportunities in transitions that weren't there before. You can see openings and submissions that weren't available before. You may have positions that you want to get to and the transition can give you the opportunity to get there.
It is in these transitions that there are numerous possibilities to alter the direction of the game. Anything can happen in these moments and in the blink of an eye, everything can completely change.
p.s. Sorry for the long break in blog postings. I'm trying to figure out the RSS feed so you'll know when I've put up a new post. Thanks for your patience.