First off there is nothing WRONG with horses. In fact there will always be a place for horses....we need them to breed mules.  ; )

I just like Mules better here is why.

Mules don't look like horses.
This is the thing about a mule that is most obvious to the casual observer--of course they look different. Well, you see, mule lovers like the look of a mule. We love those magnificent big ears and long goofy face. We love to watch those ears flop in a relaxing rhythm on a relaxing ride, or prick rigidly forward when the mule spots something interesting.  We enjoy being different, knowing that a mule will draw attention where only the most outstanding and expensive horse will stand out from the crowd.  We like they way a mule sounds, too—kinda silly, but fun. It makes me smile or laugh every time my mule brays.

Mules are loaded with personality.
Mules are smarter than horses by far.  Mules learn things (Good or bad things) often times when they only see them 3 times.  Mules are smart enough to not do things they think are dangerous. Mules have a personality of their own that I just don't see as much of in horses. They are friendly, caring animals, as long as you treat them right. For example my Mule Star will often come running to the gate and jump up and down like a dog wanting attention or if he thinks its time to go for a ride. 

Mules have their own time clock

The mule has an amazing ability to tell time. When worked on a regular basis he can tell break time, feed time or quitting time within a few minutes, if these breaks take place the same time on a daily routine.  

Mules endure heat better than horses do.
It has been scientifically proven that the donkey is similar to the camel in its ability, when water starved, to drink only enough water to replace lost body fluids. Most mules inherit this ability. Water founder in a mule is so rare as to be notable when it does occur.

Mules have fewer feeding problems than horses do.
Many farmers keep their draft and work mules together in pens with feed available at all times, yet the mules rarely overeat to the point of colic or founder. Mules require no fancy hay—just plain, clean, fresh hay suitable for equines.

Mules eat less than horses do.
Mules that are not working usually don't need grain at all. Good pasture or clean hay is the usual maintenance ration

When mules are working, their grain ration is usually about 1/3 less than that of a horse of the same size.

Mules rarely have hoof problems.
Mules naturally have small, upright, boxy feet—which is part of the secret of their surefootedness. Mules that work on pavement, stony ground, etc. are shod, but most pleasure animals, or mules that work on softer ground, never see a shoe. Regular hoof trimming keeps them just fine. Their feet are strong, tough, flexible, and usually not as brittle and shelly as those of a horse. They have less of a problem with splitting, chipping, and contracted heels.

Mules excel in physical soundness.
Mules last longer, are more "maintenance free," and are less expensive at the vet's office than horses are. Leg problems are far less likely in a mule than in a horse, and when leg problems do occur, they are far less severe. Parts of the mule including his hide are tougher and more durable than comparable parts of the horse.

Mules live longer productive lives than horses do.
Farm mules average 18 years to a horse's 15 years. When the mule is a companion animal doing lighter work and getting better medical care, better feed, and good management, the mule can give its owner good riding at age 30; 40-year-old retirees are not at all uncommon. I own and ride a 28 year old mule who can out perform and recover faster after climbing big hills than our 6 year old paint

Mules have a strong sense of self preservation.
This is one good reason why mules physically last longer than horses do. If they are overheated, overworked, or overused for any reason, mules will either slow down to a safe pace or stop completely. Mules are not stubborn. Neither are donkeys. Yes, if you want them to work too hard for their own well being, especially in hot weather, they will be "stubborn." We have never heard of a messenger running a mule to death the way legends say they ran their horses! The facts that mules are inclined not to panic, that they think about what is happening to them, and they take care of their own physical well being prevents many accidents that might happen if they were horses. Also mules often inherit the Donkey fight response to danger instead of the horse flight response to danger.  If a horse is scared and isn't sure what has startled it the horse will usually run from the scary thing (this is a flight response and can lead to a thrown rider or injured horse and rider). A mule will most often when frightened spin in place to face the threat to fight first and run second.  This gives the mule time to see what it was that scared it and usually realize its not a threat. This response can often keep the other mules and horse from running if they are behind the mule. The same horse who runs off out of control at the front of a trail ride can cause other animals to panic run.

Mules are surefooted and careful.
Their surefootedness is partly physical and partly psychological. On the physical side, the mule has a narrower body than a horse of the same height and weight. He gets this from the ass side of the family. His legs are strong and his feet are small and neat. This narrow structure and small hoof configuration enable him to place his feet carefully and neatly. On the psychological side, mules have a tendency to assess situations and act according to their views (most of which have to do with self preservation). I often let my mule pick the safest way down a bad path.  The trail rides that go down into the grand canyon only use mules to carry people down the very narrow rocky paths that are usually long deadly drops to the bottom. Picture in your mind, a narrow trail winding down the wall of the Grand Canyon, a string of riders on mules. Where each mule places each foot is critical. He does it from memory. The mule cannot see his feet, but he anticipates where each foot has to go as he moves forward. Horses do the same, but the mule is much better at it.   Most things I have heard and read say mules are better on all four feet than a horse is on its best two.  The bad side to this is a mule can kick with all four hooves more accurately than a horse with its best two.