Harry Potter: The Worst Thing Every Order Of The Phoenix Member Did

Arabella Figg is revealed in the 5th book in the series to be a squib: the daughter of a wizard and witch that possesses no inherent magical abilities of her own. That, of course, does not mean that she is useless.

Growing up in the magical world, Mrs. Figg is extremely knowledgeable, and Albus Dumbledore puts that knowledge to use by installing her as the elderly neighbor of Harry, charged with keeping watch over the Dursley's home as he came of age.

There is speculation as to why Mrs. Figg was selected for this role. Perhaps her lack of magic would make Harry difficult to track by outside forces while her knowledge would enable her to be suspicious of events, such as the presence of Dementors in Little Whinging.

What it does not excuse, however, is Mrs. Figg's insistence on being no one of note to Harry. Even times in which he went over to her house, often at the insistence of the Dursleys when they wished to go out without him, she not only did not divulge any of Harry's heritage, or the world he'd one day join, but made it an absolute chore to exist in the same room with her and her many, many cats. This was a time when Harry desperately needed a friend more than anything, something she failed to provide.