My external hard drive sometimes decides not to turn on with my computer. Time machine tries to make a backup, but fails. After ten days of trying to make backups it pops up a warning telling me it hasn't been able to make a backup in ten days.
This is a desktop computer. It isn't like I travel away from home with it where it can't connect to a time-capsule. I would like a warning the first time it is not able to make a backup.
I believe, but have not verified that the time capsule icon in the menu bar changes when it isn't able to make a backup. However that is too subtle for me.