It is pretty simple really... Unconditional love is not a part of swinging.
If Mrs Spoo lost her incredible figure, I would still love her madly/blindly. I am in love with who she is through and through and nothing on the outside can change that. On top of that, I am convinced that she has the same love for me. It is important to stay in healty for her - but a part of me realizes that if I am not perfect, she loves me anyway.
And in a marriage like that - it is easy to get comfortable - and, sadly, somewhat sloppy. It isn't a great reason, but it does happen. I am beyond impressing her with my "outer attributes"; in the words of Prince, "She Loves Me For Me."
Swinging doesn't have that. People don't
LOVE you - they lust for you... They might very well like you - but up front that is hardly important. They are hot for you - they dig you - they want you. That is all the consideration you get in most cases. So - the package is often more important than the contents.
Say what we want about personalities - if there is not some sort of physical attraction the best you are going to get is stimulating conversation. They don't care that your back hurts so you can't exercise or that you have a cute little weakness for chocolate - all they care about is do you trip their trigger...
With that sort of "pressure" - in that sort of environment - your body is your tool. You either bring your "A" game or you settle for "the best you can get." Personally, I enjoy the game - and just like the NFL has a training camp; and in training camp champions are made - swinging has plenty of incentive to "hot up". Sometimes, one more hour on the treadmill is the difference between you going to a room or the other guy going.
I know this sounds very shallow - and maybe it is - but the sex in swinging often is fairly shallow, very surface - based on the most basic attractions and urges. Friendship - as much as we sincerely desire it - is rare. We learned this lesson early. It is not often that someone wants to sit down and find out that you are a fascinating conversationalist - they want to find people to play with.
If that chemistry happens - good for us! Beyond that is just the bonus; the icing on the cake. And it just doesn't happen in swinging without first wadding into the shallow end...
Spoomonkey