Anyone who has played Pryzm will know how precious clarity is. It usually only keeps depleting. However, there are various items scattered around the world, such as the voice recorder above. When found, it INCREASES clarity by 20. The challenge is that the location of such items is changed with every New Game.
You can certainly attempt to find them by revisiting stages, but each visit costs more and more clarity. So there needs to be a decision whether you want to search for them as part of your strategy or to head straight for the end goal.
There are some items that remain in the same area, such as the diary above. Spoiler hint:The key to the door it is located behind is in the very same house, so you only need to redo that scene once if you didn't find it the first time. Definitely worth the clarity spent, even with a pesky enemy encounter.
Be warned. There are some items and paths that DECREASE clarity. Not everything is worth picking up when making a run (unless you want to unlock a specific path, discover lore, or get item achievements). If you know something reduces clarity, don't pick it up again! But you will NEED certain key items to get the best ending in True Pryzm...