Although it's mostly down to practice and untraining, I'd second the idea that lack of confidence in the absorbency of the nappy is a major inhibiting factor. During my first year or so of full-time wear, although most wets happened freely there were still a few situations where I couldn't wet without concentration. The more absorbent the nappy, the less likely I was to have difficulty, and the breakthrough occurred when I started wearing premiums - ABDL brands or Maxis - all the time. Once I had the subconscious reassurance that there was always a good safety margin of absorbency, and lots of experience of leak-free wear, wets started happening effortlessly anytime, anywhere. Maybe put on something thick and thirsty and practice letting go of a full bladder in a safe environment, gradually working towards a more and more public setting. Each step will help build your confidence that it's OK and safe to do whatever you need in the nappy wherever you happen to be.