In a totally silly vein:
Think of it this way ...(in my mother's voice.... ahem):
What if you get hit by a car ... and live, young man? Hmm? . .Well, actually, what if you're hanging between life and death .... laying there in your hospital bed with both legs and arms in plaster casts? You'd look up at the ceiling and think about all the joys and regrets of your life (and whether or not you were wearing clean underwear at the time of the accident).
Wouldn't one of the regrets in your mind be (timpani sound here, please)...THOSE 20 SHEETS OF FILM YOU NEVER DEVELOPED? .
Would you think, "I should have developed that film .. I SHOULD have developed that doggone film! Or would you think, "Hey, lighten-up Mom! You'll kill me with guilt long before I ever die from this accident".
There. Now, if this doesn't motivate you ... um, I wouldn't blame you.
(sorry... it's late here)