This is an absolute must-have feature and a glaring oversight in this product. There is no warning or other indication that custom fields become PERMANENT. Why can we not remove a custom field? It makes absolutely no sense.

So far we know about Custom Fields, and now I realize that Product Records also cannot be purged (they can be made inactive, but no way to remove them from the system, even if they were never referenced in any invoice)!

What other elements in QBO are PERMANENT (cannot be deleted)?