Broken references
A tracked item can point at configuration that isn't part of your workspace. Mochi surfaces these under Needs a look so they don't slip by.
Configuration in Aprimo is full of connections: a content type uses a field, a field belongs to a group, a rule leans on a classification. When a tracked item points at something that isn't part of your configuration, Mochi flags the reference. It happens two ways.
A missing dependency
The referenced item is real, it just isn't tracked yet. This is the common one: an item gets tracked before the pieces it depends on. The referenced item still lives in one of your environments, so the fix is to bring it in and make your configuration complete. See Repair broken references.
A broken reference
The referenced item doesn't exist in any of your environments. The pointer leads to something that isn't there, so there's nothing to bring in. The fix is to change or remove whatever points at it.
How Mochi surfaces them
Both show up under Needs a look in your configuration. Mochi names the item doing the pointing, never a raw internal id, so it's clear what the reference is and where it belongs.