Perhaps I'm just not as confident that no one else would ever figure it out, or perhaps I'm not so good at concealing it. Personally I don't want anyone else to know, but those whom I choose to let know, and I don't want anyone else to have to even "guess" about any suspicious bulges.
For my own self, I can now only recall two specific incidents where I tried to discreetly wear a diaper in front of others, and this is what happened: As I recall, I left both incidents wondering whether or not I had been detected, with no sense of certainty on this. Afterwards I reasoned, "Do I want to have to always wonder in such cases, whether or not my relationship with so-and-so was negatively affected by my ‘little secret?'"
At that point shortly after these two particular incidents, I simply decided that I wanted to keep that element of uncertainty out of my work relationships and out of my normal social relationships. Personally, I would not want to accidentally detect any stranger or loose acquaintance practicing any aspect of their own fetish in front of me, or having to deceive me about whatever it was that they were doing (saying they were saying incontinent when they were not), so why should I expect that of them? I would feel like too much had been asked of me.
So I made that decision when I was in my 20s, and now approximately 40 years later, I don't regret it one bit. Others may make other decisions, and I can never know all of the variables that cause them to make their own decisions. So that was my decision, for whatever it may or may not be worth.
Yooda
PS: Personally, I feel that those of us who can carry on their lives as normally as possible, taking care not to offend anyone else around them regarding their "preference," make the best ambassadors for our kind. Personally, my sexuality is a part of my life that I like to keep as private as reasonably possible, and completely out of view of all but those who are the closest to me. The sexuality of others is also something I would just as soon not know about in most cases, any more than necessary. Perhaps that makes me a "stuck up prude," but hey, I do happen to like prunes very much!