"skidding" is good because you learn the limits of traction and also how to control the bike when it looses traction
grabbing your back brake and locking your rear wheel isn't any good, but a wet slick leaf strewn road and a bike with slicks is.
you don't need brakes (you might call that "drifting" then)
try riding switchbacks fast with the back end out, that is faster than the "other" line…..
if you are riding fast enough, your tyres WILL loose traction – FACT!
watch sam hills cornering technique for how its done