I just remembered that there was a time when I tried to keep a diary. I still have it somewhere, but the last entry is several years old. The point is that I was too bored to bother with a chronicle about my day-to-day life. The only times when I really felt the urge to write a diary was when I was feeling down, so it turned out to be kind of depressing.
When I dug out my teenage diary years later it was all about how my life sucked. I quickly slipped it back into the drawer again. It was a good excercise in getting things of my chest, but the possible audience didn’t even include myself. Writing for an audience of no one seemed a waste of time anyway.