I am like this...sometimes!
I started a piano quintet some months ago with four professional musicians. In the beginning, I practiced lots and lots on my part...bu then, as we had rehearsals so seldom, and most often they were cancelled (last one was two months ago) I lost motivation to practice on this. Tomorrow, we are supposed to go through the mov. 1-3, and I have not recovered the practice!
So, a bit later today...I will try to go through them all...if I can find the sheets. I am totally horrified.
I can say i definitely do the same thing, though not usually musically related, since i just play for myself. It really is ridiculous some of the stupid excuses that i come up with not to do things. hahaha, but then i find i always preform best (at work, not really musically) under pressure so i guess its my own way of making sure i do a good job WHEN i get around to doing it. at least thats what i tell myself to justify it!
Lead me, Follow me, or get out of my way!
~General George S. Patton