There’s one fan theory floating around that Augusta purposefully gives Neville Frank’s wand because it will make him look untalented. Before their torture and hospitalization, Neville’s parents Frank and Alice were popular and powerful wizards who fought against Voldemort (played on-screen by Ralph Fiennes), and according to one Redditor, Augusta might have wanted to keep Neville’s real talents quiet.
As u/samsg1 wrote on a thread, “Augusta (Neville’s Gran) surely expected that Neville, too, would grow to be a powerful wizard and she may have anticipated Voldemort would come back someday, or that Neville might want to avenge his parents and become an Auror himself someday, and decided to sabotage her son’s magical ability to protect him. So instead of buying Neville a wand for himself from Olliviander’s (surely coming from a seemingly well-respected and old pure-blood family she had the galleons) she decided to give him Frank’s old wand knowing Neville would struggle to use magic to his full potential.”
Other users admitted the theory was compelling, but pointed out a few flaws. First, Neville frequently mentions that Augusta is disappointed that he isn’t more like his father, and second, she’s not necessarily wealthy just because the Longbottoms are a pure-blood wizarding family. Most convincingly, though, is the fact that before his father’s wand breaks, Neville has been furiously training alongside Harry and the student vigilante group Dumbledore’s Army — because the Death Eaters who tortured his parents break out of the wizarding prison Azkaban, and Neville probably wants to avenge Frank and Alice himself.
