I try, though everyone is different in how they approach moderation and so you can have a diverse team, but different interpretations of things like spam.
As an administrator, you should offer some guidelines and training to your staff so moderation is indeed consistent. No one likes a forum where staff are unclear about what's allowed or not.
I always ensure that there are guidelines in place not only for members but also for staff members as well so that everyone knows where they stand and understands the rules and what is allowed and not allowed and how to approach an issue if one should arise.