Just from my limited experience, it's possible for people to be working on multi-year projects that may not bring in much or any money but which have the strong

Just from my limited experience, it's possible for people to be working on multi-year projects that may not bring in much or any money but which have the strong potential to grow. On the flip side, it's possible for an employee to claim he's 'bringing in' $X while he's simply maintaining work that was developed by someone else. Trying to to draw a line from revenue to your work is something you like to do if it is favorable and not if it's not (I've been in both positions). OTOH raises are about retaining people and the relative differences between who gets a raise is usually about who's more important to the future of the group and / or who is harder to retain / replace.