When can friction not be useful?

Answer 1

friction is generally useful only if u consider the instances of walking and writing using the friction between pen and paper but otherwise it is mostly not useful as an example the parts of a machine can get regularly damaged due to friction in between the various parts and reduce its life

Another contributor wrote: We can learn a lot about the natural attributes of friction from nature. Nature, over millions of years, has adapted to various environments both to use friction and avoid its "un-useful" effects. For example, friction wears down joints between bones in the human anatomy. However, to avoid damaging friction, the body utilizes remarkable articular cartilage -- 80% water suspended in a porous material -- to absorb blows and reduce friction. While remarkably durable, over time, friction can wear away at the cartilage eventually creating pain and Arthritis. So, in this instance, friction is both good and bad. The friction between feet and the ground produce movement, but the friction between the joints can eventually produce the failure of those joints.

Friction enables birds to fly, snowflakes to grow, and Gazelles to run; but it also slows down the universe, creates damaging heat in electronics and wears down the tires on your car.

It is both positive and negative -- an asset and a liability. The trick is to make it work for you while minimizing its negative affect.
Anytime you want speed.
when is "friction" not usefull
There are a lot of times where you do not want any friction, like if you go Bowling. Or if you like to play curling.
When you want travel at a constant speed for example.

If an object was at a constant speed and you wanted it to stay at that speed without a resultant force, there would have to be no friction (and no drag). This would be useful as it wouldn't require energy to stay at that speed. Free energy, but it doesn't exist unfortunately.

Answer 2

It generates heat which causes somethings to burn!!!!!!!!!!!!!!!!

Answer 3

When spinning wheels hydroplane atop water's lattuce... the speed causes the rotation of the tires on the surface to breifly act as a , e.x. sheet of ice and a skidding effect happens...

Answer 4

It slows things down, which is a problem because sometimes you want something to not slow down, like an industrial machine.