... if you feel that you need an excuse, that is :-P
i would say "i have a problem with my bladder." it's not a lie! my reliable, predictable, and pain-free bladder is of annoyingly high capacity and releases only when i tell it to! unless i wait way too long, in which case it ceases to remain pain-free, so i figure that's typical. all of which means:
(1) i have never been in a situation where i honestly need diapers. i've been drunk and on sleeping pills and on muscle relaxers (no, not at the same time!) and haven't experienced any accidents. and
(2) when my body informs me that i need to pee, a standard diaper is insufficient. if i just simply release and ignore what i'm doing and just let it happen (which is one of the best feelings ever) the amount and speed of such will overwhelm my diaper and it's leak city.
so, i don't have a "bladder problem". my bladder works great. my problem with my bladder is that sometimes, when i'm wearing a diaper, it works too dang well. :-)
do you have an excuse too?