Marketo notifications: Idle trigger campaigns clean-up
Marketo has an excellent service that automatically deactivates dormant triggered campaigns with no activity in the past six months. Marketo does this sweeping once every quarter, and this essentially helps speed up the overall system.
Well, life is all roses and rainbows until Marketo deactivates non-operational campaigns (e.g., old event registration campaigns), but there's a fair chance that any of the operational campaigns could get deactivated in this process as well.
Marketo does log a notification in the notification area a week before the idle-campaign deactivation and also when it's done with the clean-up. However, in a busy instance that usually logs a lot of notifications on a daily basis, it is possible for marketers to miss notifications.
As a best practice, one of the first things I do upon getting into a new instance is to subscribe to all the key notifications via email, including the "Idle Trigger Campaign Cleanup" notifications.
This saves me a ton of time by eradicating the need to regularly sift through the notifications, thereby helping me focus more on building stuff.
As a side note, if you regularly see a lot of your operational campaigns included in the idle campaign deactivation list, I'd highly recommend you spend some time thinking about whether you really need those campaigns.