something been bothering me

This is actually explained in the lore. The entity feeds off survivors hope. It's in her full interest to keep her preys alive, and this is noticeable in the fact that she can resurrect sacrificed survivors and erase most (but not all, as from the diaries of Benedict Baker) of their Memories. If survivors could remember what happened, they would lose their hope and just try to commit suicide by any necessary means during the trials, becoming useless after just a wrong trial for the entity. It's also hinted that survivors that denifitely lose every spark of Hope becomes killers, at some point, but this may be yet to be confirmed (gameplay-wise).

And so having wounds, scratches, Memories of their pain and sacrifice may help them fully remember. It may be possible that survivors who escape the trials untouched with all of their partners could retain their memories about that particular trial, because despite being not satisfying for the entity, it would surely boost their hope.

This is also noticeable gameplay wise when ranking as a killer, because obtaining a 4K score in a very short time doesn't satisfy the requirements to get iridescent emblems, and is somehow considered a punishment for the killer.

Last but not least, remember prestige skins for survivor include bloody and sloppy versions of their standard appearence. To achieve a rank 3 prestige you have to play lots of trials as that survivor (or have lots of BP), so this may represent, my mind canon, their memories and experiences of the trials that slowly start to come together, and the power of the entity to erase their mind to slowly loose grip. This also explains how is it possible for survivors to bring items like a flashlight with specific add-ons that increase blinding time. If they didn't knew about this possibility, by seeing it first person, they would probably choose a medikit instead.

Hope i gave you enough to think off for your question