Simple way to explain the difference between 250k and 500k Pots.
Using 250k pots with single-coil pickups provides a warmer, darker tone, while 500k pots yield a brighter, more open sound by allowing more treble frequencies to pass through to the amplifier. 250k pots are often preferred for single coils, like those found in Strats and Teles, to tame their natural brightness, where as 500k pots are a common choice for humbuckers to compensate for their inherent warmth and lack of treble.