Some people think that brickbreak is weaker than earthquake.

Well, that's true.

A BIT TRUE.

Cause when a fighting pkmn uses brickbreak, its stronger than earthquake.

Let me explain myself:

If a pokemon uses a move that is the same type as the user's type, its 1.5 times as strong! When its super-effectiv on your opponent the move's power is increased again. The same story for crictical-hit.

Example:

A normal type uses explosion(type mach x 1.5)and it is a crictical-hit(x 1.5) and it is super effective agaist opponent's type 1(x1.5) and type 2(x1.5) than its having a power of 1898.4375!

Conclusion:

Its better for a blaziken to use brickbreak than earthquake!