One thing I enjoyed with the recent Longshot Saves the Marvel Universe series was the idea of just how far the effects of Longshot's luck powers reach, for good or ill. Usually, when comics show people with probability powers, we see them work for a specific moment in time, and that's it. The Scarlet Witch waves her hand, something weird happens, the moment passes, there are no ripples. What Hastings did was go with the idea that the effect wouldn't just stop there. That if the altered probability involves other people, then their lives will continue to be impacted by it long after the initial, highly unlikely event took place.
At one point, Longshot recalls a moment where he crashed through the roof of a house with a jetpack. He was all right, good fortune for him, but it created problems for the family, which ultimately fell apart. The husband didn't deal with it well. The mother and daughter ended up coming to visit their friend, who happens to be the daughter of Dr. Dipson. And the daughter's stuffed bear wound up as the safe haven of the Cosmic Cube, keeping it from either half of the In-Betweener, helping Longshot set things right.
Longshot's powers are only supposed to work if his motives are pure, but the trick is that even with pure motives, that doesn't guarantee happy results for everyone. His powers cause of some rich mogul to randomly appear in front of that salon where he gets his hair done. Great for them, bad for the salon across the street that goes out of business, and can't even find a buyer for the space. And because of his psychometric powers, Longshot can see the results of his actions.
Think of the weight that could place on him. All heroes have to deal with the idea that every decision has consequences. Turn right and stop a mugging, miss the car accident that they would have stopped if they went the other way. But Longshot can affect lives, bring them joy or ruination without actively doing anything.
Maybe that's why he keeps getting his memories wiped. He has to approach the world with a clean slate, because otherwise, he'd never be able to use his powers. The risk of unintended consequences, of altered probabilities running to their ultimate end could cripple someone with doubts, or make it impossible to act with pure motives. Imagine Tony Stark with probability altering powers. He'd unleash some 217-step process that made him God King of the Universe that began with causing Captain America to spontaneously develop a peanut allergy while enjoy PB&J. Peter Parker would probably never do anything, because he'd be paralyzed by the chance it would hurt innocent people. Longshot is sort of aware of the possibilities, but just naive enough to roll with it. Those long-term ripples are just a little too much for him to keep track of, so he uses his powers (mostly) to try and help, but doesn't get hung up entirely by the idea that one person's fortune is another's misfortune.