As there is a maximum number of quests that can be active in your quest log at any one time, this could be useful. Especially if you wanted to perform your class quests first and then go back to perform any side quests or have picked up a lot of weekly/daily quests at fleet..
Yes I finished all my story missions passed many side missions up and now they don't show up unless im right on top of that region.Quite annoying I gotta run around the entire map and find them again to que them up.Cause technically they've already been "discovered"