Brake hard and you feel the front of the car dip down and the rear rise - that is brake dive. It is a normal physics effect, but excessive dive can point to suspension wear. Here is what brake dive is and when it matters.
Weight transfer under braking
When you brake, the car's momentum shifts weight forward onto the front wheels, compressing the front suspension and lifting the rear - the nose dives. This is why front brakes do most of the work and are larger than the rears; more weight is pressing the front tires into the road; see do heavier cars need bigger brakes.
Some dive is normal
A moderate amount of dive is completely normal on any car with conventional suspension - the softer the suspension, the more dive. Performance cars use stiffer springs and anti-dive geometry to reduce it. So a bit of nose-dip under hard braking is nothing to worry about.
Excessive dive can mean worn parts
If the front end dives dramatically or bounces after braking, worn front struts or shocks may be the cause - they are not damping the weight transfer. That is a suspension issue, not a brake fault, but it affects braking stability and tire grip. Worn suspension paired with braking can also worsen a pulsation feel.
Brakes vs suspension
Brake dive itself is not a braking problem - the brakes are doing their job. If dive is excessive, have the front struts/shocks checked. Keep the brakes themselves sharp with quality pads, good rotors, and fresh hardware for confident, controlled stops.