- few or no posts had been made for a long time
- journal was a deleted or inactive journal of someone now using a new and different journal
- journal had a lot of quizzes and friends' list surveys that detracted from or replaced substantive posts.
- "other" (this applies to exactly two journals, and if you have to ask, they aren't yours).
If I dropped you, please know that I wish you well and enjoyed reading you when you were on my list.
I'll probably add a few as well...