My group has just ended their Rogue Trader with a "season finale" giving me time to rest from that heavy management system and the crazy adventures. We started Deathwatch 2 weeks ago, mainly getting characters built and a brief intro adventure, which will conclude this week.

My question will likely seem like a "duh" question but I want to be sure I am on the right track.

When constructing missions you have Primary, Secondary(s) and Tertiary(s), which helps determine renown rewards, threat levels and requisition.

How do you brief the players?

Meaning, do you brief them on all Primary, Secondary(s) and Tertiary(s) aspects of the mission or do you keep some of them "hidden" as they might discover/stumble upon them later in the mission?

Example: Mission Alpha (1 Primary, 2 Secondary, 3 Tertiary). Watch Captain briefs the team on Primary, Secondary Missions. However, during the course of the mission, the team stumbles upon different avenues of investigation that may aid Primary/Secondary mission accomplishment.

When constructing missions you have Primary, Secondary(s) and Tertiary(s), which helps determine renown rewards, threat levels and requisition.

How do you brief the players?

Meaning, do you brief them on all Primary, Secondary(s) and Tertiary(s) aspects of the mission or do you keep some of them "hidden" as they might discover/stumble upon them later in the mission?

I always lay out all known Objectives during the Mission Briefing. Any 'bonus' Objectives that might crop up during the mission don't modify Requisition, thus forcing the players to think carefully if they want to expend finite resources pursuing them to earn extra cudos.

You should always have the overall measure of success spelled out. Specific objectives change as the chaos of events ensue but the players should always have a clear beacon (kill all the aliens, protect X at all costs, Don't allow Y...etc) to follow.

Agreed. The players should always know going in what the theoretical objectives are, but there should always be at least something else worth their time once they hit the ground to avoid it being move to X, kill, move to Y, kill, move to Z, kill, win.