effective braking
Normally wheel braking is most effective throughout the entire speed range.Reverse trust is most effective at higher speeds,typically speeds above 100kts. Reverse trust can sometimes be more effective than wheel brakes on wet and slippery runways. Like reverse trust,speed brakes provide aerodynamic braking at higher speeds.They also assist wheel braking by dumping lift,thereby putting the entire aircraft weight on the wheels, earlier in the landing roll.