Section signals are strings appended to the end of a Section Name on a page layout. These section signals communicate configuration instructions that are carried out by custom Veeva pages both online and offline.
But even though the user adds the section signals on the page layout, they still do not work.
The section signals are not evaluated because the user does not have permissions of any fields in that section.
The user needs to have, at least, one field Field-Level Security (FLS) to be able to see the section and evaluate the section signals.
CRM Help Documentation: Section Signals