Disappearing Voice Pages

I've noticed for a while that it seems that there are some voice pages that disappear. I understand that some may be removed by the user or because they are not in favor of the community. However it seems that perhaps there is a glitch in the system that purges voice pages?

Here's a list of three voices pages of mine that disappeared:
http://stackideas.com/voices/easysocial/item/564
http://stackideas.com/voices/easysocial/item/721
http://stackideas.com/voices/easysocial/item/625


Perhaps there is a hidden record for these? Below is three links that correlate to the voice pages.

http://stackideas.com/forums/cleaner-url-s-through-all-of-easysocial
http://stackideas.com/forums/photos-centralized-within-a-single-menu-item
http://stackideas.com/forums/group-custom-fields

All three of those had a decent amount of supporters/votes and was aimed directly to create the greatest good for the greatest number of people.