They really need to put in the mission description that you must do the STF from the beginning to end to get the reward. I helped run some people through Cure Friday and 3 of us got the borg deflector, but two did not because they hadn't done the first space part. One of our teammates had told them that they would still get credit for doing the STF even though they joined us on the ground. Obviously they were mad when they didn't get credit for doing the STF because they have to do it again and had just wasted 3 hours on a lie.
All missions have a list of objectives which are usually in the window along the right side of the screen. if you come in the middle of ANY mission without completing the objectives that came before it, you will not get credit nor the reward for doing it.