Well, "F" mostly, that is why LilMak sent the case of "Old Spice" to you.

I like jumping in your missions and try to when ever you post one. There are a few things you might do different to help with the success rate of your missions, but on the whole you do a good job, thats why I dont mind jumping in.
For me not to join one is only because I'm in the middle of something else either in the game or at home (afk for bits of time doing stuff around the house).
I think one of the biggest issues with the missions is lack of success. This discourages players from "investing the time" in one. I think a lot of players just figure ganging a base with "everyone else" is a better way to succeed.
Todays players are more about the "kill" than "playing the game" in my opinion. Thats why you'll come in at 15k with your buffs after a well planned out route and find a certain squad hovering around in tempest and F4-U4s to pick as the mission comes in. They are looking to add to their kill totals not a fight to defend the base. You can tell that because as soon as you get one in a bit of trouble "dive out and RTB" is there plan every time.
Missions use to be part of the game because most players were playing at being a WWII pilot and living the "Glory days" if you can call WWII the glory days. We were all pretending to be William Holden, Alec Guinness, James Garner, Matthew Modine, Michael Caine and all those other great movie heros. Todays players not so much.