From the introduction: These are minor annoyances, so they don’t need to be super-carefully controlled. If something from this list gets you killed it’s because of a cascade of effects—a loose strap leads to reduced AC which leads to being hit when you wouldn’t have, just when you are low on Hit Points—it’s not just an annoyance, it’s an annoyance at a terrible moment (for want of a nail, the kingdom was lost). But mostly, these are just little flavorful things to remind players that while a giant trying to crush your head is a serious problem for a few seconds, a hole in your only pair of socks is much more likely to bother you for a long week of adventuring.