Friction is helpful for these sports:
Friction is not helpful for these sports:
Friction is important for all sports.Without it it becomes really hard to accelerate or deaccelerate.For example a 100m sprinter.It would be great for him if there wasnt any air resistance (as long as he can breath).But he needs friction on the floor to push himself forward.however friction is less useful in hockey, skiing, and almost all types of boarding(snowboarding, wakeboarding, kneeboarding, sandboarding).
Friction is not useful in activities like ice skating and skiing, where minimizing friction allows for smoother and faster movement. Similarly, in sports like sailing and swimming, reducing friction with the water is essential for efficiency.
Ice skating does not require any friction because the skater needs to glide on the ice and if there was any friction on ice the skater would have trouble to skate smoothly on the ice. That is why ice skating does not require any friction at all from my perspective.
Your knee
Brakes are meant to have a lot of friction and it's useful.
Friction is sometimes not useful as when a player drives forward in a wet condition the ball slows down due to the friction so it is harder to control and difficult to get a shot away. Also a player can lose momentum during fast strides or slip in wet conditions. The ball will slow down because of the friction with the grass so it is easier for the goalkeeper to save it.
No Friction Runes Computers
the friction from pushing the hull through the water is not useful as long as you're travelling.
It can be useful when a ball is catching
how does friction help car tyres?
Sandpaper is high in friction but is not considered useful in terms of being helpful in a general sense.
stopping cars Friction is useful to start a fire with sticks.