I have a Yaesu FTM-400XDR, but this applies equally to at least the FTM-100 series and probably other radios.
When you program memory channels/frequencies, you can select one of three options: Select, Skip and Off(blank).
Select is obvious - in memory scan mode, the radio scans these program settings and ignores all others.
Skip vs. Off/Blank is eluding me however. What is the functional difference between them? Is there some mode in the radio where they act differently?