Lol - that just means they're below an F.
An F is a sub-optimal moveset on a decent/good Pokemon. If it's not listed, it means it's a sub-optimal moveset on a sub-optimal Pokemon. For the most part if you only see one set of moves then the Pokemon isn't worth using otherwise. I'm sure they did it in the interest of saving time.
Air Cutter is a horrible charge move. Quite literally worthless b/c it actually has lower DPS than your quick move (and a massive cooldown)....so most DPS calculations just ignore it.
Karate chop isn't horrible on Magmar, but he's just not a great Pokemon to begin with...especially when considering A) he's the worst fully evolved fire Pokemon (although Rapidash is damn close), and B) Fire Pokemon just aren't great in this meta with so many strong Water Mons. So if you're going to use him, you might as well pick the best moveset
