Silence at the edges is cut for you
When you press Stop, the voice recorder looks for quiet at the start and the end. A stretch below −50 dB that lasts at least 0.3 seconds is removed, and 0.1 s of it stays so the first word isn’t clipped. Want every second? Turn off “Remove silence at the edges”. A pause in the middle is easy to cut later in the MP3 cutter.