While recording a PB, a double tap can be interpreted as a single tap (don't know when it happens... but it happened to me... maybe after 3min of not utilisation of the Apple Watch it goes to some "sleep" mode, so that the 1st tap is only "waking up" the watch?). This stops the recording... maybe to avoid this, or also unintended taps, you can add a "Yes/No" confirmation?