I did fuck the wife earlier and l asked her to put her legs up in the air behind my back.
She was happy to do it but complained l cum too quickly.
So as many have said l think WG’s do this to make guys cum quickly.
So you've either asked her to do this before and proven her point, in which case
you have a problem that needs addressing for her satisfaction OR she's a woman of eminently more sexual experience than you and perhaps you'd best confirm she's learned the efficacy of alternate positions before marrying you.
Putting legs up behind your back can either inhibit your thrusting or give you better access depending on how you adjust your angle of penetration in response.
Putting legs up in front of you generally allows for greater penetration and also allows the woman to possibly obscure your face.
Just because you cum more quickly does not mean a woman is trying to make you finish sooner, she may be trying to get something from the encounter which you failed to deliver on. Your assumption that she's trying to con you points to your own inadequacies and lack of sexual ability and control.