This is why one has some broad general rules for keeping and maintaining a zettelkasten. It helps to have some rules to practice and make a habit.

Unmentioned here is that true artists known all the rules and can then more profitably break those rules for expanding and improving upon their own practice. This is dramatically different from what is seen by some of those who want to have a commonplace or zettelkasten practice, but begin without any clear rules. They often begin breaking the rules to their detriment without having the benefit of long practice to see and know the affordances of such systems before going out of their way to break those rules.

By breaking the rules before they've even practiced them, many get confused or lost and quit their practice before they see any of the benefits or affordances of them.

Of course one should have some clear cut end reasons which answer the "why" question for having such practices, or else they'll also lose the motivation to stick with the practice, particularly when they don't see any light at the end of the tunnel. Pure hope may not be enough for most.