In the Harry Potter universe, a recurring theme is that some wizards are more powerful than others. For instance, Voldemort is considered to be an immensely powerful wizard, and so is Dumbledore.
However, I struggle to see how exactly this power could be quantified, or what exactly it would mean for a wizard to be more powerful than another.
Do any of the books mention how power is quantified? Or how a wizard becomes more powerful?