Inconsistent validation of price field and option visibility combinations
See https://github.com/civicrm/civicrm-core/pull/13966 for early discussion. Basically, CiviCRM occasionally attempts to prevent you from creating a price field with Admin visibility that only has options with Public visibility or vice-versa. It is by no means consistent or effective in stopping this, however.
Some people hold the opinion that there should be no validation on this. At the very least, the validation should allow you to fix situations where there is no price option with visibility that matches its field's visibility (the situation that PR 13966 fixes).