Regarding directional tires, and the dangers of incorrect tire rotation and mounting them backwards:
These will have a V-shaped tread pattern that acts to pump water and mud away from the center line of the tire. These tires are better able to handle heavy rainstorms and slushy snowfall by actively pushing water out to the sides of the tread area as the tire rolls forward, minimizing the risk of hydroplaning at high road speeds in heavy rain.
And even if you do start hydroplaning, water is pumped out by the V-tread as you slide forward on the water layer, allowing you to regain traction more quickly than a non-directional tread.
Off-road and tractor tires can have such large and deep V-treads that the tire changes to look like it has angled tread slabs or paddles on a bald tire surface, allowing the tire to pump thick and heavy mud out of its path.
The deeper and wider the V-tread channels, the greater this pumping action, but a large-grooved V-tread is also going to have less torque transfer to the ground and reduced braking traction since the grooves takes away contact surface of the tire to the ground. A large-grooved tread may also wear faster since more vehicle weight is concentrated over a smaller tread-to-road contact area.
The V-groove will also work to drive fine granulated sand out of the tread path. If you go into a uncontrolled skid on dry sandy pavement, some of the sand will get pushed out to the sides through the V-tread and assist in regaining traction more quickly, vs a non-directional tread that will just trap and roll the sand forward in the tread grooves.
So, you do not want to mount these tires backwards because then that V-tread will work against you, instead pulling any water, mud, or sand on the road into the tread path and trying to concentrate it there. The result is that you are likely go into uncontrolled hydroplaning at freeway speed with even a light rainfall, and the vehicle may be unusable in moderate to heavy rainfall unless you drive very slowly.
The unidirectional tread pattern generally has no safety impact on moving in reverse in wet weather, because a typical vehicle can't go fast enough in reverse for the inward water-pumping action to have much effect.