To "peel the onion," so to speak...
Cheaters want the end result so bad: The prestige and personal satisfaction of being declared "a winner."
They need this and it drives them so that they simply can't enjoy the experience. They can't accept losing because it really makes them feel insecure.
In their own convaluded logic, cheating is just another strategy to employ so they can prove they were smarter, craftier than other people. In a weird sense of denial, their actions are justified. Consider Capt James T Kirk, who altered the rules of the winless game in Starfleet Academy to allow him to win. Amazingly enough, cheaters all seem to fantasize that they are #1 Federation Starfleet Commander as well, and that they must best people any way they can. How many Kirk wannabes are out there? Many.
Not being able to handle losing is insecurity. It is tremendously disrespectful to other pleyers, some of which I am happy to say are friends, although I've never met them.
Personal challenge, comeraderie, and enjoyment take precedence over the simple temptation of cheating, which appeals to us all on some level. Most solid players realize that a victory via cheating is empty. You haven't really tested yourself.
When you are mature enough to handle losing, you don't get mad and curse for the death of the victor. You appreciate them, learn from them, and congratulate them. Well, maybe you swear a little.
This is a game, simply put. Enjoy the experience, good or bad. Revel in what you have done well, and work on what you need to do better. It is ok to lose. Percentages are heavily stacked against you.
When a cheater fantasizes that the game it represents a chance to prove they are not a "loser," they blatantly prove otherwise without really acknowledging it.